Poplar is an important timber and shelterbelt tree species. The soil drought severely limits its growth, development and quality. Deciphering the theory and production for drought resistance is of interest on the poplar varieties cultivation, arid land use, and ecological environment construction to evaluate poplar full sib family drought resistance and select drought index. In this study, 123 progenies derived from a cross of Populus deltoides. ‘Danhong’ × P. simonii. ‘Tongliao1’ were subjected for moderate pot water control experiment via determining 12 growth parameters such as photosynthesis, leaf and water indexes. In addition, we established field experimental forest and measured one year growth increment. The results showed that all tested traits represented significant changes under the drought conditions in relative to the control. The drought stress severely modified stomatal conductance (Ga) than other traits (P<0.01). Correlation analysis indicated that responsive traits exhibited different degrees of correlation. Drought resistances of the progenies at seedling stage were evaluated with principle component analysis and subordinate function. The hybrid population were classified into three types as drought sensitive type、moderate drought resistance type and high drought resistance type with each contained 30、72、and 21 individuals. DX-27、DX-4、DX-3 and other seven lines adopt to drought better than male parent P. simonii. ‘Tongliao1’. Line DX-55 and DX-81 got the maximum drought resistance D value (all 0.60), and showed the strongest drought resistance. Stepwise linear regression and correlation analysis indicated diameter (D), net photosynthesis (Pn), stomatal conductance (Ga) and transpiration rate (Tr) could be used as drought resistance index of which Ga has the most large direct effect on drought resistance. The comprehensive evaluation was used to analyze field growth characters, and classified progenies into 4 types. Populus deltoides. ‘Danhong’ and P. simonii. ‘Tongliao1’ belong to the first and fourth class, respectively. Six lines（DX-76、DX-78、DX-53、DX-55、DX-3、DX-20）possess better drought resistance ability than male parent P. simonii. ‘Tongliao1’ belong to the first and second class, and regarded as drought resistance and fast growth material, preliminarily. Thus, this research provided theoretical basis in breeding for drought resistance in poplar and tests for drought resistance at the seedling stage.