Objective To observe the effects of progesterone on the paw mechanical withdraw threshold (PMWT), spinal cord neurokinin‑1 receptor (NK‑1R), and plasma substance P expression in rats with incisional pain, and to explore the possible mechanism of progesterone on the pain. Methods According to the random number table method, 24 healthy adult male Wistar rats were divided into three groups (n=8): a control group (group C), a progesterone group (group P, intramuscular injection of 1.5 mg/100 g 3 h before operation), and a mifepristone group (group M, intragastric administration of 1.5 mg/100 g 3 h before operation). An paw incisional pain model was established according to Brennan's method, and the PMWT of the injured paw was measured at four time points: before administration (T0), before operation (T1), 1 h after operation (T2), and 3 h after operation (T3). Western blot was used to detect the level of NK⁃1R in the spinal cord, and enzyme⁃linked immunosorbent assay (ELISA) was used to determine plasma substance P at T3. Results Compared with that in group C, PMWT in group P and group M increased at T2 and T3 (P<0.05), and PMWT in group P was higher than that in group M (P<0.05). Compared with group C, the levels of spinal cord NK⁃1R and plasma substance P at T3 in group P and group M decreased (P<0.05), and the levels of spinal cord NK⁃1R and plasma substance P in group P were lower than those in group M (P<0.05). Conclusions Progesterone can inhibit incision pain, which may be related to its binding with the progesterone receptor to inhibit the expression of NK⁃1R and the production and (or) release of substance P.