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[Objective]The aim of this paper was to screen Paspahim dilatalum germplasms with strong drought resistance, and provide theoretical basis for the breeding and promotion of drought resistant germplasm. [Method] A drought simulation pot experiment was carried out with six P. dilatalum germplasms, and then the changes of various physiological indexes under drought stress were evaluated by means of principal component analysis and membership function. [Result] Under drought stress, the malondialdehyde contents of all the six germplasms gradually increased from the start to the 21st day, then a sharp increase was observed during 21st -28th days. The peroxidase activity, catalase activity,and soluble protein content increased first and then decreased,reached the maximum at 14 day,with one exception that the soluble protein in P. dilatalum germplasm coming from Meitan, Guizhou reached the maximum at 7th d. The total soluble sugar content displayed a significant upward trend,while the chlorophyll content showed a significant downward trend. The results of principal component a-nalysis showed that the cumulative contribution rate of the first three principal components reached 92.64 % ,which could be identified as a comprehensive index for drought resistance evaluation. Comprehensive evaluation of drought resistance showed that the drought resistance of the P. diliilatum germplasm from USA was the strongest,followed by the one from Anlong (grass slope) , Guizhou, the one from Vietnam was relatively weak, and the other germplasms rank in the medium position. [ Conclusion ] In the breeding and promotion of drought-resistant P. dilaUitum germplasms, American P. ddalatum germplasms with stalwart drought resistance should be selected priorly. [ABSTRACT FROM AUTHOR]