Compared to 32QAM technology, 32APSK technology reduces the number of amplitudes and is suitable for a nonlinear channel in a relay satellite communication system. TCM technology combines channel coding and multi-level modulation,doesn't increase the spectrum bandwidth, decreases the transmission power, cuts down energy consumption, lowers the requirements for technical indexes of the power amplifier, and is beneficial for achieving lightweight and miniaturization of satellite payloads. This paper combines 32APSK technology and TCM technology, proposes a kind of 32APSK-TCM technology, discusses details of the 32APSK-TCM technology constellation subset splitting method and constellation point selection method, and analyzes the performance of the 32APSK-TCM technology. This paper simulates the 32APSK-TCM technology and 16APSK technology using the simulation platform of the relay satellite communication system developed by our research team. Simulation results demonstrate that under the condition of an ideal channel, I/Q amplitude phase imbalance, amplitude frequency characteristics, group delay, phase noise, power amplifier saturation point, and nonlinear channel, if the maximization value of the required bit error rate is 1E-6, compared to 16APSK technology, the minimization value of the signal-to-noise ratio of 32APSK-TCM technology saves 13.29 dB, 13.29 dB, 14.84 dB, 15.54 dB, 15.11 dB, 15.77 dB, and 16.37 dB, respectively.