Aiming at the problem of sea surface temperature (SST) measurement in radar power prediction (RPP), a modification method of sea surface temperature is proposed based on infrared sensor. The measured deviation of infrared sensor for SST is analyzed. The infrared models of sea surface radiation and reflection are modeled. The affections of sky radiation to result of SST and RPP are analyzed by simulation. A modification method for RPP is deduced. Through experiment, the result shows that the relative error of prediction result is limited in 20% with 80% probability by this method, which greatly enhances the prediction accuracy.