Lawyer: Zhang borrowed 50,000 yuan from Li and issued an iou. There is no agreed repayment time. Wang signed a letter of guarantee in the column of guarantor that day. How to determine the warranty period in this case? Readers in Feng Qiang, Feng Qiang: The guarantee period refers to the beginning and end time when the guarantor assumes the guarantee responsibility. The guarantor shall bear the guarantee responsibility within the prescribed time limit, and beyond that time limit, the guarantor will no longer bear the guarantee responsibility. When the parties agree on the guarantee period, they should pay attention to the following points: first, the guarantee period should be calculated from the expiration of the independent contract, and it is not appropriate to set the guarantee period earlier than or equal to the debt performance period; Second, it is not appropriate to stipulate the guarantee period as indefinite. The guarantor shall assume the guarantee liability on the premise that the debtor fails to perform the debt, and the guarantee period shall also be counted from the expiration of the main debt performance period. If the creditor and the debtor have not agreed on the time limit for the performance of the principal debt, it is difficult to determine the starting point for the guarantor to assume responsibility. If the time limit for performance of the principal debt is not agreed, it shall be determined in accordance with Article 88 of the General Principles of the Civil Law and Article 66 of the Contract Law, that is, "If the time limit for performance is not clear, the debtor may perform the debt to the creditor at any time, and the creditor may also ask the debtor to perform the debt at any time, but the other party shall be given the necessary preparation time". After the creditor proposes a reasonable grace period, it will determine the original unclear performance period of the principal debt and clarify the starting point of the guarantee period. Article 33 of the Supreme Court's Interpretation on Several Issues Concerning the Application of Guarantee Law stipulates that if there is no agreement or unclear agreement on the performance period of the main debt in the main contract, the guarantee period shall be counted from the date when the creditor requires the debtor to perform its obligations. Article 26 of the Guarantee Law stipulates that if the guarantor of joint and several liability guarantee and the creditor have not agreed on the guarantee period, the creditor has the right to require the guarantor to assume the guarantee responsibility within six months from the date of expiration of the independent debt performance period. If the creditor fails to require the guarantor to assume the guarantee responsibility during the guarantee period agreed in the contract and the guarantee period stipulated in the preceding paragraph, the guarantor shall be exempted from the guarantee responsibility.