Single sideband communication is one of the important research fields of modern communication technology, and its purpose is to improve communication signal-to-noise ratio and spectrum utilization, so as to improve the reliability, stability and efficiency of signal transmission. In this paper, a single sideband AM signal demodulation circuit is designed based on Simulink, which shows and analyzes the modulation and demodulation process of single sideband AM signal concisely and intuitively. At the same time, the influence factors of noise are considered, and the influence of different variance and mean of Gaussian noise on the signal is studied. The simulation results show that the designed demodulation circuit can effectively demodulate the original information in the single sideband AM signal. On the basis of adjusting the mean and variance of Gaussian noise, it is concluded that larger mean and variance of Gaussian noise will lead to distortion of output signal.