Abstract: Since human beings had architectural activities, indoor is the main place for people to live, and people began to demand indoor environment. With the progress and development of society, the requirements for indoor environment are constantly updated, developed and enriched. The task of interior design is to comprehensively use technical means, consider the role of surrounding environmental factors, make full use of favorable conditions and give full play to creative thinking, so as to create an indoor environment that not only meets the functional requirements of production and life, but also meets people's physiological and psychological requirements. Keywords: interior decoration 1. Interior decoration design elements 1. Spatial elements. The basic task of design is to rationalize the space and give people a beautiful feeling. We should be brave in exploring the new image of space endowed by the times and technology, and don't stick to the spatial image formed in the past. 2. Color requirements. Indoor color not only affects the visual environment, but also directly affects people's mood and psychology. Scientific color selection is beneficial to work and health. Proper color processing can not only meet the functional requirements, but also achieve beautiful results. In addition to observing the general color rules, indoor colors are different with the changes of aesthetic standards of the times. 3. Light and shadow requirements. Humans love the beautiful scenery of nature, and often introduce sunlight directly into the room to eliminate the darkness and closed feeling, especially the top light and soft scattered light, and make the indoor space more intimate and natural. The change of light and shadow makes the room more colorful and gives people a variety of feelings. 4. Decorative elements. The indispensable building components in the whole indoor space, such as columns and walls, need to be decorated in combination with their functions to form a perfect indoor environment. Making full use of the texture characteristics of different decorative materials, we can obtain a variety of different styles of indoor artistic effects, and at the same time reflect the historical and cultural characteristics of the region. 5. Display elements. Indoor furniture, carpets, curtains, etc. They are all necessities of life, and their shapes often have the characteristics of furnishings, mostly playing a decorative role. Practicality and decoration should be coordinated with each other, and the functions and forms should be unified and diverse, so as to make the indoor space comfortable and decent and full of personality. 6. Green elements. Greening in interior design has become an important means to improve the indoor environment. Planting flowers and trees indoors, using greening and sketches to communicate indoor and outdoor environments, expanding the sense of indoor space and beautifying the space have positive effects. 2. Basic principles of interior decoration design 1. Interior decoration design should meet the functional requirements. Interior design aims at creating a good indoor space environment and puts people's requirements for indoor production, life, work and rest in the first place. Therefore, indoor design should fully consider the functional requirements to make the indoor environment reasonable, comfortable and scientific; We should consider the law of human activities and deal with the spatial relationship, spatial size and spatial proportion; Reasonably allocate furnishings and furniture, properly solve indoor ventilation, lighting and lighting, and pay attention to the overall effect of indoor color. 2. Interior decoration design should meet the requirements of spiritual function. Interior design must also consider the requirements of spiritual functions (visual reflection of psychological feelings, artistic infection, etc.). ) at the same time consider the functional requirements. The spirit of interior design affects people's emotions, even their will and actions, so we should study people's cognitive characteristics and laws; Study people's emotions and will; Study the interaction between man and environment. Designers should use various theories and means to impact and influence people's emotions, sublimate them and achieve the expected design effect. If the indoor environment can highlight a certain artistic conception, then it will have a strong artistic appeal and better play its spiritual function. 3. Interior decoration design should meet the requirements of modern science and technology. The innovation of architectural space is closely related to structural modeling. They should be coordinated and unified, fully consider the image of beauty in structural modeling, and integrate art and technology. This requires interior designers to have the necessary knowledge of structural types, and be familiar with and master the performance and characteristics of structural systems. Modern interior decoration design belongs to the category of modern science and technology. Only by making full use of the latest achievements of modern science and technology can interior design better meet the requirements of spiritual function. 4. Interior decoration design should meet the requirements of regional characteristics and national style. Due to the differences in geographical, geographical and climatic conditions, the living habits and cultural traditions of various ethnic groups are different, and there are indeed great differences in architectural styles. China is a multi-ethnic country, and the differences of regional characteristics, national character, customs and cultural literacy of all ethnic groups make the interior decoration design different. Design should have its own different styles and characteristics. It is necessary to embody national and regional characteristics in order to arouse people's national self-esteem and self-confidence. 3. Key points of interior decoration design: The interior space is bounded by the ground, the wall and the top surface, which determines the size and shape of the interior space. The purpose of interior decoration is to create a suitable and beautiful indoor environment. The floor and walls of the indoor space are the background of people, furniture and furnishings, and the difference of the top surface makes the indoor space more varied. (1) floor decoration-floor decoration is very important in people's field of vision. The floor has more contact with people and the sight distance is close, which is one of the important factors of indoor decoration. The design should meet the following principles: 1, and the floor should be in harmony with the overall environment, learn from each other's strengths and set off the atmosphere. From the perspective of the overall environmental effect of the space, the base surface should be coordinated with the ceiling and wall decoration, and at the same time, it should play a role in setting each other off. 2. Pay attention to the segmentation, color and texture characteristics of ground patterns. The ground pattern design can be roughly divided into three situations: the first is to emphasize the independence and integrity of the pattern itself, such as the conference room, and to express the importance of the meeting with cohesive patterns. The color should be coordinated with the meeting space to achieve the effect of quiet and concentration; Second, it emphasizes the continuity and rhythm of the pattern, which has certain guidance and regularity, and is mostly used in halls, walkways and public spaces; The third is to emphasize the abstraction of patterns, which are free and changeable, free and lively, and are often used in irregular or freely arranged spaces. 3. Meet the needs of floor structure, construction and physical performance. Pay attention to the floor structure when decorating the base surface, which will bring convenience to the structure and construction on the premise of ensuring safety. We can't pursue the pattern effect unilaterally, but also consider the needs of physical properties such as moisture-proof, waterproof, heat preservation and heat insulation. There are many forms of base surface, such as wood floor, block floor, terrazzo floor, plastic floor, cement floor and so on. The design patterns are diverse and colorful, which should be consistent with the whole space environment and complement each other in order to achieve good results. (2), wall decoration. In the indoor visual range, the wall is perpendicular to people's line of sight and is in the most obvious position. At the same time, the wall is the part that people often contact, so the decoration of the wall is of great significance to interior design, and the following design principles should be met: 1, integrity. When decorating the wall, we should fully consider the unity with other parts of the room, so that the wall and the whole space become a unified whole. 2. Physical. The wall occupies a large area in the indoor space, plays an important role and has higher requirements. The requirements for sound insulation, heat preservation and fire prevention of indoor space vary with the nature of the space used. For example, the requirements for hotel rooms are higher, while those for general unit canteens are lower. 3. artistry. In indoor space, the decorative effect of the wall plays a very important role in rendering and beautifying the indoor environment. The shape, partition pattern and texture of the wall are closely related to the indoor atmosphere. In order to create the artistic effect of indoor space, the artistry of the wall itself can not be ignored. The choice of wall decoration forms should be based on the above principles, and there are roughly the following forms: plastering decoration, facing decoration, brushing decoration and coil decoration. This paper focuses on coil decoration. With the development of industry, more and more coiled materials can be used to decorate walls, such as plastic wallpaper, wall covering, glass fiber cloth, artificial leather, leather and so on. These materials are widely used, flexible, colorful, good in texture, convenient in construction, moderate in price and rich in decorative effects, and are widely used in interior design. (3) ceiling decoration. Ceiling is an important part of interior decoration, and it is also the most varied and eye-catching interface in interior space decoration. It has a strong sense of perspective. Through different treatments and lamps, the appeal of the space can be enhanced, and the top shape is colorful, novel and beautiful. Design principles. (1), pay attention to the overall environmental effect. The ceiling, the wall and the base form an indoor space together, and * * * together create an indoor environmental effect. Attention should be paid to the coordination and unity of the three in design, and each has its own characteristics on the basis of unity. (2), the top decoration should meet the requirements of applicable beauty. Generally speaking, the effect of indoor space should be that the top decoration is simple and complete, highlighting the key points, and at the same time, the shape should have a faint sense of pleasure and art. (3) The top decoration shall ensure the rationality and safety of the top structure. We can't simply pursue modeling and ignore safety. 2, the top surface design form. (1), flat top. This kind of suspended ceiling has simple structure, elegant appearance and convenient decoration, and is suitable for classrooms, offices, exhibition halls and so on. Its artistic appeal comes from the shape, texture, pattern and organic configuration of lamps and lanterns on the top surface. (2), concave and convex ceiling. This kind of ceiling is gorgeous in shape and strong in three-dimensional sense, and is suitable for dance halls, restaurants, corridors and so on. Attention should be paid to the primary and secondary relationship and height difference relationship of each concave-convex layer, which should not be changed too much, and the sense of rhythm and the artistry of the whole space should be emphasized. (3), ceiling. Hanging various folded plates, flat plates or other suspended ceilings under the load-bearing structure of the roof is often used in gymnasiums and cinemas to meet the requirements of acoustics, lighting and other aspects or to pursue some special decorative effects. In recent years, this kind of suspended ceiling is also commonly used in restaurants, teahouses, shops and other buildings, which makes people have special aesthetic feeling and interest. (4) Well ceiling. It is a kind of suspended ceiling that combines the form of structural beams, the interlacing of primary and secondary beams and the relationship of TIC-tac-toe beams, and is equipped with lamps and plaster flower patterns, which is simple and generous and has a strong sense of rhythm. (5), glass ceiling. This form is often used in the foyer and central hall of modern large public buildings, mainly to meet the lighting and indoor greening needs of large spaces, making the indoor environment more natural and adding vitality to large spaces. Its shape is usually dome-shaped, conical and folded. In a word, interior decoration design is a comprehensive subject, involving sociology, psychology, environmental science and many other disciplines, and there are still many things we need to explore and study. This paper mainly expounds the basic principles and design methods of interior decoration design, hoping to discuss with design colleagues. If it is incorrect, please criticize and correct me.