In order to find out drought resistance of broomcorn millet cultivars under the different ecological environment, to excavate the drought of genetic resources, to provide drought resistance of materials, field direct identification method was used for drought resistance identification of 56 broomcorn millet cultivars at adult stage on the study in Dunhuang City, Gansu where annual rainfall is less than 40mm. By paired analysis, drought stress was no significant to nodes of main stem, panicles per plant, straw weight per plant, main panicle length, 1000-grain weight, specific leaf weight, on the contrary, plant height, spike weight per plant, grain weight per plant, yield per plot, Flag leaf area, leaf area index, period of duration reached a significant level. On the basis of system cluster result of drought resistance index and comprehensive evaluation value D, screened two cultivars named Longmi No.2, Longmi No.1o with better drought resistance; By gray correlation analysis, flag leaf area, 1000-grain weight, panicles per plant, yield per plot can be used as adult stage drought identification index.