Objective To explore the effect of sitagliptin preconditioning on the NOD‑like receptor 3 (NLRP3)/cysteine aspartic acid specific protease‑1 (caspase‑1)/gasdermin D (GSDMD) signaling pathway in rats with mechanical ventilation associated lung injury (VILI) models. Methods A total of 36 specific pathogen free (SPF) grade, healthy Sprague‑Dawley (SD) male rats, aging 6‒8 weeks were selected. According to the random number table method, they were divided into three groups (n=12): a control group (group C), a high tidal volume model group (group V), and a high tidal volume ventilation+sitagliptin group (group S). Tracheotomy was performed in all the three groups. Then, group C maintained autonomous respiration for 4 h, while group V and group S received mechanical ventilation for 4 h. Then, 1 h before tracheotomy, rats in group S were intraperitoneally injected with 100 mg/kg sitagliptin, while those in group C and group V were intraperitoneally injected the same volume of normal saline. The partial pressure of oxygen (PaO2) and glucose levels in the arterial blood of the rats were detected before tracheotomy and after mechanical ventilation or autonomous respiration for 4 h. Then, the rats were sacrificed and their blood samples were collected to detect the concentrations of IL‑1β and IL‑18 in the serum and bronchoalveolar lavage fluid (BALF) by enzyme‑linked immuno sorbent assay (ELISA). The gross appearance of lung tissue was observed, the pathological morphology of lung tissue was observed by H‑E staining under a light microscope, and lung injury scores were evaluated. The wet/dry (W/D) of lung tissue was detected. Western blot was used to detect the levels of NLRP3, GSDMD, apoptosis‑related speck protein (ASC), and caspase‑1 in rat lung tissues. Results Group C showed nearly normal morphological structure of pulmonary alveoli in rats, while completely destructed pulmonary alveoli were seen in group V, with alveolar breakage and fusion, alveolar septum edema, much inflammatory cell infiltration, and alveolar hemorrhage. Compared with group C, group V and group S presented dark red on the surface of lung tissue to various degrees, with congestive edema. Compared with group V, bleeding and edema were relieved in group S, with scattered bleeding points, weakened pulmonary interstitial edema, less inflammatory cell infiltration, and reduced injury degree. Compared with group C, group V and group S showed increases in lung injury scores, W/D, the concentrations of IL‑1β and IL‑18 in the serum and BALF (P<0.05), the levels of NLRP3, GSDMD, ASC, and caspase‑1 were up‑regulated in lung tissues (P<0.05), as well as decreases in PaO2 after mechanical ventilation for 4 h (P<0.05), while group V presented increased glucose level after mechanical ventilation for 4 h (P<0.05). Compared with group V, group S showed decreases in lung injury scores, W/D, the concentrations of IL‑1β and IL‑18 in the serum and BALF (P<0.05), and the levels of NLRP3, GSDMD, ASC, and caspase‑1 were down‑regulated in lung tissues (P<0.05), with elevated PaO2 (P<0.05) and reduced glucose level (P<0.05) after mechanical ventilation for 4 h. Conclusions Sitagliptin can inhibit pyroptosis, reduce the release of inflammatory mediators, and alleviate VILI in rats, which may be associated with down‑regulating the NLRP3/caspase‑1/GSDMD signaling pathway.