Objective To explore the effect of nitroglycerin on ET/NO, TXA2/PGI2 and pancreas pathomorphology changes in severe acute pancreatitis (SAP) rats. Methods Sixty SD rats were random divided into five groups, including control group (A group, n = 12) and experimental group(B,C,D and E group, n = 12). The SAP was induced by injection of 5% sodium taurocholate through retrograde common biliopancreatic ducts via duodenal papilla with epidural catheter. Group C, D and E were intravenously injected with nitroglycerin 0.5μg/kg/min,1μg/kg/min and 2μg/min in 30 min respectively, and group A and B was injected with Sodium Chloride 0.5ml. The indexes of changed pathomorphology and ET/NO, TXB2/6-keto-PGF1a, were determined at the 6th and 12th hour after operations, respectively. Results The specimen data of the 6th and 12th hour displayed that the indexes of changed pathomorphology, ET, ET/NO, TXB2, and TXB2/6-keto-PGF1a of the group C,D and E degraded respectively, compared to group B(P < 0.05). Conclusion The nitroglycerin could degrade ET, ET/NO,TXA2 and TXA2/PGI2, improve the microcirculation of pancreas, and delay the pathological inflammation change in SAP rats.