With twelve peanut cultivars grown under artificial water control, the drought resistance related physiological and biochemical traits and the drought resistance mechanism of peanut leaves were studied. Two water treatments were designed, that were 50% and 70% of the soil relative water content of the 0-80 cm soil layer, respectively, at pod-setting stage. The results showed that the twelve peanut cultivars could be grouped into three different resistance levels based on their yield drought resistance coefficient. The A596, Shanhua 11 and Rugaoxiyangsheng were grouped as cultivars with high resistance, while Huayu 20, Nongda 818, Haihua 1, Shanhua 9 and 79266 with moderate resistance, and the ICG6848, Baisha 1016, Hua 17 and Penglaiyiwohou with weak resistance. The mechanism of high drought resistance in peanut cultivars of A596, Shanhua 11 and Rugaoxiyangsheng were due to more powerful antioxidant capacity, higher activity of photosystem II (PS II) and photosynthetic rate (Pn). By contrast, the moderate resistant cultivars Haihua 1 had stronger antioxidant protection capability, and the Shanhua 9 had much higher PS II activity. The Pn, stomatal limitation value (Ls), maximal photochemical efficiency of PS II (Fv/Fm), photochemical quenching coefficient (q(p)), content of malondialdehyde (MDA), relative electric conductivity and superoxide dismutase (SOD) activity of leaves were very significantly correlated with the drought resistance coefficient. Therefore, they were important indicative traits for the drought resistance at pod-setting stage of peanuts. These traits could be evaluated under normal irrigation condition except that the SOD activity should be identified under drought stress. Based on this study, we proposed that Shanhua 11 and 79266 could serve as standard cultivars of high drought resistance and weak drought resistance, respectively. Shanhua 11 could also serve as a standard cultivar for identification of leaf drought resistance traits in peanut.