Purpose: The aim of present study was to investigate the protective role of melatonin (Mel) against 10 GHz microwave radiation induced adverse effects on testes of mice. Materials and methods: 6-8 weeks old 24 male Swiss albino mice were procured from inbred colony and were divided into 3 groups. Group I Sham exposed (control), Group II microwaves (MW) exposed, Group III (MW + Mel) treated with melatonin (2mg/kg body weight). The power density was measured 0.25 mW/cm2 and the SAR was calculated 0.12 W/kg. Results: After completion of exposure period the animals were sacrificed and testes were excised to study various stress related parameters. Analysis of data revealed that long-term 10 GHz exposure resulted in significant decrease (P < 0.001) in Superoxide dismutase (SOD),Glutathione peroxidase (GPx) and testosterone whereas Catalase (CAT), Malondialdehyde (MDA) and ROS increased significantly(P < 0.001). Meanwhile, melatonin reversed adverse effects of MW radiation and it increased SOD, GPx, testosterone and decreased CAT, MDA and ROS significantly in MW + Mel group (P< 0.001). Conclusion: It may be concluded that free radicals causing oxidative stress could be responsible for detrimental effects in testes whereas, melatonin proved to be a strong antioxidant and it reversed the adverse effects of MW radiation.