In China, Asset/Liability Management (ALM) has been put into practice, however, loan interest rate is still controlled by the central bank, that leads to some difficulties for commercial banks in designing credit contracts. In the paper, a model is set up, trying to explain some credit behaviors of banks to small-medium enterprises in China. When borrowers' collateral values are so low that banks could not sort borrowers by offering sorting credit contracts, credit cherishing would occur. Asymmetry information between banks and enterprises, high investment risks and low collateral value of enterprises are the key factors to bring credit cherishing in China.