Abstract: Objective: To investigate the mechanism of cells apoptosis in rabbit with acute lung injury(ALI) induced by blast. Methods: Forty rabbits were randomly divided into the control group(n=10) and experimental group(n=30). The ALI model of rabbit was established by air blast. After 4, 12 and 24 hours of lung injury, the cells apoptosis of injury tissue were detected using the wet/dry weight ratio(W/D) of lung, PaO₂ and TUNEL, the levels of caspase-3, Bax and Bcl-2 were detected using immunohistochemistry and the pathological morphology were observed under microscopy in 10 rabbits each time-point. Results: The pulmonary interstitial and alveolar edema, a large number of red blood cells, inflammatory cells and serous effusion in alveolar space, and pulmonary interstitial thickening were found in experimental group under light microscope. Compared with the control group, the W/D and PaO₂ in experimental group increased and decreased significantly, respectively(P<0.01), The apoptosis index, caspase-3 and Bax/Bcl-2 in experimental group were significantly higher than those in control group(P<0.05 to P<0.01). Conclusions: Apoptosis plays an important role in the occurrence and development of ALI, which is involved in lung tissue injury and promoting the development of ALI.