Cognitive electronic warfare requires smarter algorithms to adapt to the increasingly complex electromagnetic environment.As to the frequency prediction for frequency-agile radar with variational parameters, a frequency prediction method based on differential evolution algorithm is proposed according to the real data and the data analysis after eliminating the outliers.The proposed method can not only improve the prediction accuracy and reduce the demand for data consistency, but also be adaptable to the variation of frequency of the tuning parameters through online analysis, thus it has higher application value and robustness.