The performance of electro-optical detection system is affected by the design of electro-optical circuit. The performance of electro-optical detection circuit is simulated based on PSpice EDA software. The PSpice model of photodiode, the characteristics of time domain, frequency domain and noise are analyzed. According to the parameter scanning function of PSpice software, the circuit parameters are optimized. Based on the noise analysis function of PSpice software, NEP and post-stage circuit design parameters of the system are calculated.