Under the condition of information asymmetry, through constructing game model, this article analyzes four equilibrium results when the rural credit union makes credit and loans to farmers. The four equilibrium results are respectively the partly successful pooling equilibrium of credit market, the entirely successful detaching equilibrium of credit market, entirely failing combination equilibrium of credit market and the nearly failing mixed strategy equilibrium of credit market. Then, the article analyzes the reasons why rural credit union is unwilling to loan to farmer. In the end, the article brings forth related suggestions such as following market interest rate, perfecting credit system and introducing the loan deputy system.