Objective: Cold exposure is associated with increased prevalence of hypertension and the related severe cardiovascular events. Aberrant activation of the nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome plays an important role in the development of hypertension. Tranilast (TR), an inhibitor of NLRP3, provides a useful pharmacological probe for exploring the role of NLRP3 in pathogenesis associated with inflammation and its potential application as a therapeutic agent. This study was designed to examine the effects of TR on NLRP3 and hypertension in rats exposed to cold environment to simulate the frigid-zone conditions. Methods and results: Sprague Dawley (SD) rats were exposed to moderate cold temperature (4±1℃), and then were randomized to receive TR or vehicle for 3 weeks, while the control group was raised under rat room temperature (RT, 23±1℃). We found that cold exposure substantially increased blood pressure, NLRP3 inflammasome level, and fibrosis in aorta, which were reversed by TR. Conclusion: TR has an anti-hypertensive property in cold environment, and this beneficial action is likely conferred by its inhibitory effects on inflammation and fibrosis. These findings suggest TR as a potential drug for the treatment of cold-induced hypertension.