Objective(s): Varicocele is an abnormal dilation in the testicular vein, which can cause hypoxia, reactive oxygen species accumulation, elevation in testicular temperature, and promote apoptosis and increase proinflammatory cytokine production. According to the varicocele pathophysiology, it is possible that a group of cytosolic receptors called nucleotide oligomerization domain (NOD)-like receptor family pyrin domain containing 3 (NLRP3) inflammasomes also involve in varicocele pathogenesis. Due to the important role of antioxidant in decreasing the testis tissue damage, in this study we investigated the protective effect of resveratrol (RES) on NLRP3 complex and apoptosis in experimental varicocele rats. Materials and Methods: In this study, 40 male Wistar rats were randomly divided into 5 groups (8 rats in each group): Control, experimental left varicocele (ELV), ELV + ethanol, ELV + 20 mg/kg RES and ELV + 50 mg/kg RES. Varicocele was induced by partial ligation of the left renal vein. Three months after varicocele induction, RESwas orally administered to rats for 1 month. The expression levels of NLRP3, apoptosis associated specklike protein (ASC), caspase-1, Bax and Bcl2 were analyzed using real time PCR. Results: Our results showed that RESat both doses significantly (P≤ 0.05) decreased the gene expression levels of ASC, NLRP3, caspase-1 and Bax and increased Bcl2 gene expression at high dose. Conclusions: RESby reducing inflammatory factors and decreasing apoptosis might be used as adjuvant therapy to reduce varicocele complication. [ABSTRACT FROM AUTHOR]