Abstract: The evaluation of postgraduates’ scientific research ability has a great role on the cultivating of scientific research professionals.According to the characteristics of mining universities, this paper selects 26 indexes to build an evaluation index system of mining university postgraduates’ scientific research ability from three aspects:basic ability, practical ability and innovative ability.In order to solve not integrated and low accuracy of evaluation methodology, this paper uses connection number of set-pair analysis to describe the uncertainty of this system, utilizes cloud model to realize the fuzzy classification of index.Besides, this paper combines two methods to build set-pair cloud model, which improves the accuracy of evaluation results.The model is applied to the research evaluation of graduate students in mining colleges.Through the analysis of the data obtained from the questionnaire, the results show that the scientific research ability of postgraduates from 211 mining universities is better than those from general mining universities, which is consistent with practical situation and has reference to the evaluation of postgraduates’ scientific research ability.