For improving utilization ratio of combat data, put forward an improved fuzzy comprehensive assessment model method. Based the basic function of combat data on decision-making, verify the necessity of combat data on the assessment methods in command and decision-making and analyze the elements influencing the assessment. Construct an index system from the quality of combat data, the function of the decision-supporting system, and the competency of commander. Then construct assessment model with the statistical method, the ROC, the fuzzy comprehensive evaluation method respectively according to the characteristics of each index, and makes appropriate adjustments to the models as well. The processed index relativity degree shows that the method assessment conclusions closer to reality and use combat data effectively.