Millimeter wave is high in path loss, strong in directivity, and is very sensitive to the obstacles caused by obstacles and the Doppler frequency shift caused by motion. Therefore, how to provide a stable link quality becomes a problem to be solved in millimeter wave communication systems. Aimed at the problems that electromagnetic waves have different propagation characteristics in consideration of the continuous increase in the number of antennas and cost, traditional multiuser precoding technology is difficult to use in millimeter wave communication systems, and the combination of millimeter wave communications with the Massive MIMO has become an important research direction for future wireless communication development, a joint algorithm of user frequency domain scheduling in the millimeter wave system is proposed based on FDMA and mixed precoding of multiple users, improving the performance in the millimeter wave communication system. The simulation results show that this algorithm is similar to the pure digital precoding in performance. Compared with other similar algorithms, the increase in computational complexity is not obvious, and the algorithm can greatly improve the performance in the millimeter wave Massive MUMIMO system.