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In our constantly changing climate, drought was the most severe natural hazard in the Heihe River Basin, which is located in the arid inland region of Northwest China. Previous studies have focused on drought and climatic change in the basin individually, but research concerning the combined effects of drought and the temperature and water vapor pressure has yet to be performed. In this paper, an analysis was proposed on the change of temperature and water vapor pressure during the drought period by utilizing linear regression analysis and inverse distance weighted interpolation based on geographic information system. According to local records of typical drought events, the characteristics of air temperature and water vapor pressure during the drought period were analyzed and the key drought period of the crop growth period was identified. The drought period was computed using the drought index of continuous non-effective rainy days based on the daily precipitation data of 14 weather stations located in the Heihe River Basin. Then, using daily mean temperature and actual water vapor pressure data, the differences in temperature and water vapor pressure in the drought, normal and no-drought periods were acquired. The key sensitive time was summer, and the sensitive areas were identified using the sensitive rate recorded at each weather station. The results showed that, during the drought period, air temperature increased and water vapor pressure decreased along with the prolongation of continuous non-effective rainy days. The respective sensitivities of temperature and water vapor pressure gradually decreased from the upstream to the downstream of the basin.