legal ground
Article 25 of the Provisions of the Supreme People's Court on Several Issues Concerning the Application of Laws in the Trial of Private Lending Cases.
If the lender requests the borrower to pay interest at the interest rate agreed in the contract, the people's court shall support it, except that the interest rate agreed by both parties exceeds 4 times the market quotation of one-year loan at the time of the establishment of the contract.
Article 28
If there is an agreement between the borrower and the borrower on the overdue interest rate, such agreement shall prevail, but it shall not exceed four times the market quotation of one-year loan when the contract is established.
Article 680 of the Civil Code
It is forbidden to lend at high interest rate, and the lending rate shall not violate the relevant provisions of the state.
If there is no agreement on the payment of interest in the loan contract, it shall be deemed that there is no interest.
If the loan contract does not specify the payment method of interest, and the parties cannot reach a supplementary agreement, the interest shall be determined according to the local or the parties' trading methods, trading habits, market interest rates and other factors; Loans between natural persons are regarded as interest-free.