Objective Explore the change of IL-1β and IL-18 expression in pulmonary hypertension induced by monocrotaline.Methods Divide the mouses into two groups, control group and experimental group (n=10).Establish rats pulmonary hypertension model induced by monocrotaline.Detect the model by ultrasound, myocardial cells HE dyeing and tunnel test;ELISA was used to detect the serum biological markers NF-κB, COX2, IL-6, IL-1β, TNF-α and NO;Immunohistochemical was used to detect the expression level of IL-1β and IL-18 in the lung tissue;the protein change of NLRP3 in the lung tissue was detected by Western blot.Results Serum biological markers of NF-κB, COX2, IL-6, IL-1β, TNF-α and NO are significantly increased in PAH rats(P<0.05);The expression of IL-1β, IL-18 in the lung tissue increased obviously(P<0.05);The NLRP3 protein expression was significantly higher in experimental group.Conclusions Changes of NLRP3 effect increase expression of IL-1β and IL-18and which may play an important role in pulmonary hypertension induced by monocrotaline.