Since the effectiveness of infrared imaging guidance simulation is determined by the validity and fidelity of typical effect modeling and simulation of an infrared imaging sensor system, it is very significant to study the evaluation method of typical effect simulation of an infrared imaging sensor system. A method for evaluating the simulation image of an infrared imaging sensor based on Structural Similarity (SSIM) and fidelity is proposed due to the shortage of evaluation method of simulation of infrared imaging sensor systems at present. In the method, the SSIM is used to evaluate the brightness, contrast and structural similarity of the simulated image while the fidelity is used to evaluate the spatial geometric characteristics and gray level distribution of the simulated image. The experimental result shows that the proposed method can evaluate the degradation effects such as blurring and noise of the infrared imaging sensor system effectively. It is suitable to verify and evaluate the quality of modeling and simulated images of infrared sensors.