This paper analyzes the incentive to deviate from the authenticity of online reviews in C2 C ecommerce by establishing the asymmetric information game model between buyers and sellers in the rules of the C2 C ecommerce platform and characterizing the evaluating behavior of the buyers in the unfair competition strategy. Results show that,with the high quality praise,the seller who took the strategy of‘Praise Reward'obtained sales increasing,as well as,it exacerbated the benefit of the buyer,which leads to hi...