Abstract The study of the optical characteristics of the marine environment and the optical imaging of the marine background by various detection platforms provide an effective way for engineering applications. By analyzing the JONSWAP spectral model, this paper constructs the height data of sea surface spectrum under typical environment, and analyses the difference of sea surface spectrum under different sea conditions. Based on the slope distribution of the sea surface, each part of the infrared radiation on the sea surface is calculated separately and synthesized by using the relationship between the position of the detector and the direction of view of the detection. The simulation model of the infrared radiation characteristics on the sea surface is established, and the distribution characteristics of the infrared radiation characteristics on the sea surface at different detection distances are analyzed.