Abstract: This study was to identify peanut’s sensitive stage to water deficit and provide theoretical basis and technical guidance for scientific irrigation and yield improvement. The mid-early maturing large-fruited cultivar ‘Yuhua 9326’ and early-maturing small-fruited ‘Yuhua 9936’ were used to investigate the impacts of drought stress on peanut yield and growth and development at four different growth stages, i.e. seedling, flowering and pegging, podding and maturing stage. The method of artificial water control in a full-automatic rainproof tank was adopted. The results indicated that water deficiency in all four stages could reduce the yield and inhibit the growth and development. The effect on flowering and pegging stage was the biggest, the main stem height and lateral branch length reduced by 42.1% and 37.5%, the yield reduction was about 22.2%, followed by the effect on seedling and podding stage, and the effect on maturing stage was the lowest. Through the analysis of various indicators, drought mainly influenced the yield at seedling, flowering and pegging stages by reducing the quality of pod; and mainly influenced the yield at podding and maturing stages by reducing the rate of plump, weight of one hundred kernel, kernel percent. This study identified that the flowering stage was the most sensitive stage to drought stress, and played an important role in water utilization efficiency in peanut production and per unit yield enhancement in arid and semi-arid areas.