The target of data mining is to extract the potential, valuable pattern or regulation in the data from a great quantity. With the fast development of computer net, the large of data of teaching evaluation is accumulated. The analysis and processing technology to evaluation data is worse than data acquisition technology, which does not satisfy the demand of fairness, justice, objective, scientificalness of evaluation. In accordance with the multi-dimension relevance and time sequence relevance of evaluation data, the paper introduces the application of data mining technology. Taking the student evaluation as example, the author uses the modified Apriori algorithm, builds the evaluation index system based on association rules, and applies theses to the practical work, and the good effect is got.