Abstract: In order to solve the problem of contradictory evaluation indexes in the process of qualitative evaluation of Kela 2 gas field in Tarim basin, the weight coefficient of evaluation indexes was determined by grey relational analysis, the comprehensive evaluation index of the reservoir was calculated. The comprehensive quantitative evaluation of the reservoirs in the Baskichik formation in the trap was carried out, the results of reservoir classification were given, and the reservoir evaluation results were verified by using the productivity data. The results show that the coincidence rate of the quantitative classification of the first reservoir of Baskichik formation is 87%, and the coincidence rate of the second reservoir of baskichik formation is 85%. The classification results are reliable and can provide the basis for decisionmaking of gas field development.