The genetic algorithms classifier and principle of classifing system of earthquake prediction based on the genetic algorithms is briefly introduced. The method to design the classifing system of shortterm comprehensive earthquake prediction based on the genetic algorithms is developed. In the method the genetic algorithms is used as the tool to optimize the prediction rules, the lasting times of abnormity is assigned as the codes; the prediction period is three months; and the seismicity is combined with many precursor methods to predict earthquake. As an example, the method is used in North Tianshan seismic zone with multiple parameters. The preliminary calculating result shows that the method has higher self-study correctness and higher ability of testing and predicting.