Abstract: Aiming at the abundant double-sided information asymmetric phenomena existing in reality,a generic model for double-sided adverse selection is constructed,in which four kinds of equilibriums,such as separating-separating,separatingpooling,pooling-separating,pooling-pooling,are put forward.Through extending the classical limited pricing model to a double-sided adverse selection under two-sided information asymmetry,four kinds of equilibriums are confirmed.In the limited pricing model of double-sided adverse selection impacts which the high-cost type entrant firm's quantity has on the equilibriums are analyzed.It is found that the high-cost type entrant firm's quantity has an effect as discount factor whose degree depends on the conditions of equilibrium under different cases.