In order to overcome the co-channel interference between neighbor cells in Long Term Evolution (LTE) system, a novel power allocation algorithm based on non-cooperative game theory is proposed in this paper. In the downlink of LTE, the pricing mechanism in the non-cooperative game theory is used to model the power allocation scheme in Orthogonal Frequency Division Multiple Access (OFDMA) cellular systems. We set the data rate as the pricing factor, and the objective function is the variance of power. Then we use Genetic algorithm to obtain the optimal solution. Both the QoS of user and the system throughput are considered in our proposed algorithm, simulation results show that the co-channel interference is reduced maximally. Comparing with the traditional water filling algorithm, the user can obtain more system throughput as the number of user increasing. It is suitable for the crowded user areas.