The performance of fuel cells is influenced by many factors, among which operating temperature is crucial. Therefore, this study focuses on analyzing the performance of fuel cells at different temperatures and optimizing operational parameters at the optimum temperature condition to enhance the performance and lifespan of fuel cells. The research finds that the optimal temperature for fuel cells is 69.9°C, with an efficient operating temperature range of 60–80°C, and the optimal flow rate range is 1000–1600 ml/min. The influence of back pressure on fuel cell performance becomes less significant when it exceeds 2.5 bar. Furthermore, this study utilizes a Gaussian process regression model to optimize the performance of fuel cells under different temperature, flow rate, and back pressure combinations. Regression analysis model predictions suggest that the optimum operating temperature is 71°C, with an optimal back pressure range of 0.9–1.4 bar and a flow rate range of 1310–1600 ml/min.