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[Objectives] his study aimed to explore the effects of drought stress on morphological changes, photosynthetic characteristics and other physiological indexes of ginger at seedling stage, and to provide reference for the study of drought tolerance mechanism and the selection of drought-tolerant varieties of ginger. [Methods] Five main varietie (‘Shandongdajiang'‘Fengtoujiang'‘Zhugenjiang'‘Luopingxiaohuangjiang'and‘Guizhouxiaohuangjiang') were selected as test materials from the main ginger producing areas of North China, Central China and Southwest China. Drought stress was simulated by 250 g·L-1 PEG-6000 solution, normal water treatment (CK) and drought treatment (DS) was set to determine the growth and physiological indexes such as leaf moisture content, leaf water potential, photosynthesis, stomatal phenotype, chlorophyll content and other growth and physiological indexes of different varieties of ginger under different treatments at 15 days, and the lignin deposition of ginger stems was observed by paraffin sectioning method. [Results] Compared with CK, the leaves of various ginger varieties had different degrees of curly yellowness at 15 days of drought treatment. The free water content (FWC), relative water content (RWC) and total water content (TWC) of leaves decreased significantly, the content of bound water (BWC) of ‘Shandongdajiang' increased, and the BWC content of the remaining four varieties decreased significantly. The water potential of the leaves of various varieties of ginger decreased significantly, and the ‘Fengtoujiang' decreased the most. In addition, the net photosynthetic rate (Pn), stomatal conductance (Gs), intercellular CO2 concentration (Ci), transpiration rate (Tr) of leaves decreased, the length and width of the stomata decreased, and the length and width of guard cells did not change significantly. Among the five varieties, the photosynthetic index of ‘Luopingxiaohuangjiang' was the most affected, and the stomatal conductance and transpiration rate decreased by 100% and 93.84%, respectively. The contents of chlorophyll a (Chla), chlorophyll b (Chlb) and total chlorophyll a+b (Chla+b) decreased but not significantly, while the content of carotenoid (Car) increased in‘Shandongdajiang 'but not significantly, and decreased significantly in the other four varieties. After drought treatment, the amount of stem lignin deposition increased in‘Shandongdajiang 'and‘ Luopingxiaohuangjiang'. [Conclusions] Drought stress affected the growth and development of ginger seedlings, and there were differences in drought tolerance among different ginger varieties. The drought tolerance of the five ginger varieties was ranked from strong to weak as follows: ‘Shandongdajiang'‘Fengtoujiang'‘Guizhouxiaohuangjiang'‘Zhugenjiang'‘Luopingxiaohuangjiang'.‘Shandongdajiang'had strong drought tolerance, which could be used for further analysis of the molecular mechanism of drought resistance and creation of drought resistance breeding high-quality germplasm materials. [ABSTRACT FROM AUTHOR]