The impact of wind power integration on the system active operation reserve is analyzed. The characteristics of operating reserve are discussed， and a risk-based reserve decision method for wind power integration is presented. A coordination and optimal reserve allocation algorithm is proposed to take full advantage of the control performance of generators， which is capable of solving the wind power impact on the operation reserve. Simulation results of an IEEE 39-bus system show that the method proposed is effective in determining and allocating the wind power reserve demands and of practical value in integrating massive active dispatch operation of the wind power system.