Legal analysis: signing a contract requires the signature of the parties. If buying and selling a house is the same behavior of both husband and wife, both parties need to sign. However, if one spouse entrusts the other spouse to sign, only one spouse will sign.

Legal basis: Civil Code of People's Republic of China (PRC).

Article 161 A civil subject may carry out a civil juristic act through an agent.

In accordance with the provisions of the law, the agreement of the parties or the nature of civil legal acts, civil legal acts that should be implemented by themselves shall not be represented.

Article 165 If the power of attorney is in written form, it shall specify the name of the agent, the matters to be represented, the authority and the time limit, and shall be signed or sealed by the principal.

Article 490 Where the parties conclude a contract in the form of a contract, the contract is formed when the parties sign, seal or fingerprint it. Before signing, sealing or fingerprinting, one party has fulfilled its main obligations, and the contract is established when the other party accepts it.

A contract shall be concluded in written form as stipulated by laws, administrative regulations or agreed by the parties. If the parties do not do this in writing, but one party has fulfilled its main obligations and the other party accepts it, the contract is established.