Abstract: Sensitivity assessment for crop drought loss is of great significance to agricultural drought risk management. Based on a soybean water deficit experiment, crop drought loss sensitivity functions are formulated in this paper by considering only the influence of current-stage water deficit on the aboveground growth of the current-stage and assuming no water deficit at pervious stages. The results indicate that the functions are roughly S-shaped over the four growth stages of branching, filling, flowering-poding and seedling. Loss in dry matter accumulation increases with water deficit intensity. At the four stages, change in the increasing rate is the fastest at the current-stage accumulated water deficit of 4.19, 4.15, 1.36 and 1.20, respectively, while the increasing rate peaks at the values of 6.37, 5.92, 2.22 and 1.87, respectively. The stage sensitivity from high to low is flowering-poding, filling, branching and seedling when the accumulated deficit is less than 7.4, and otherwise it is filling, flowering-poding, branching and seedling.