Regarding the problem of radiator threat assessment under incomplete information, an assessment algorithm based on IOWA-TOPSIS is proposed.Firstly, in view of the incomplete information of enemy radiator which is easy to occur in actual combat, the Induced Ordered Weighted Averaging (IOWA) null value estimation algorithm is introduced to predict the missing data based on the correlation of attribute sets.Then, Criteria Importance Through Intercriteria Correlation (CRITIC) is used to analyze the influence degree of different attributes on the assessment process and assign weights objectively.Lastly, the threat degree of different radiator is measured by Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) algorithm, and the threat level is ranked.The simulation results show that the algorithm can effectively evaluate the threat of radiator, and the results are more objective and accurate than those of traditional assessment methods.