In order to solve the problem of slow signal processing speed of satellite receiving system in military information reconnaissance, a satellite signal channelization scheme based on GPU is designed. Using digital down conversion cascaded multiphase channelization to improve the flexibility of sub-channel bandwidth location; Two-dimensional Block multiplexing is designed to process the multichannel down conversion process in parallel. A multiphase filtering kernel based on shared memory is designed to perform the weighted stack operation in 72 channels channelization. The test results of NVIDIA RTX 2060 and Intel(R) Core(TM) I5-6400 in CUDA environment show that the 288 channel channelization of four 75M real signals takes 4.51s in parallel processing, which is 40.27 times faster than that of single CPU processing. It greatly improves the processing speed of the receiving end of reconnaissance satellite.