Objective To investigate the effect of intra-abdominal hypertension(IAH) on respiratory function in pigs.Methods Twelve pigs were randomly divided into two groups (n=6 in each group),ie.IAH20 group(intra-abdominal pressure=20 mm Hg) and IAH30 group(intra-abdominal pressure=30 mm Hg).Pig model of IAH was established by intraperitoneally injection of carbon dioxide.The changes in respiratory function parameters including pulmonary dynamic compliance（Cdyn），peak inspiratory pressure(PIP) ,SpO2 and PaCO2 were recorded at different time points.Results Cdyn was significantly decreased at different time points compared with baseline in group IAH30 and group IAH20.PIP significantly increased at different time points compared with baseline in both IAH groups，but group IAH30 was more severe than group IAH20. No significant changes of SpO2 and PaCO2 were found in two IAH groups.Conclusion IAH can impair respiratory function by decreasing lung compliance and increasing inspiratory pressure.