Curculigo orchioides Gaertn. is a precious herb used in traditional medicine systems in Asian countries for various health benefits. This study investigated the potential protective effects of C. orchioides extract on reproductive health under heat stress conditions in male mice. Forty-eight mice were divided into eight groups, control condition (C group), C. orchioides extract at the dosages of 100, 200, and 400 mg/kg/day (C100, C200, C400 group), 40 °C heat exposure (H group), and combined 40 °C heat exposure and C. orchioides extract at the dosages of 100, 200, and 400 mg/kg/day (HC100, HC200, HC400 group). The result shows that the mice that received only C. orchioides extract without heat stress do not have a significant change in histological structure and testosterone level. The histological analysis of testicular tissue showed that heat stress conditions reduced reproductive function and inhibited the spermatogenesis of male mice. The C. orchioides rhizome extract treatment attenuated the heat stress-induced spermatogenesis complications in the murine model. Mice in the heat-stress group treated with C. orchioides extract had increased spermatogenic cells and spermatozoa compared with mice exposed to heat without C. orchioides treatment. Moreover, the aqueous extract of C. orchioides rhizome enhanced the serum total testosterone levels in heat-exposed mice. In conclusion, the study findings validate that C. orchioides is effective against heat stress-induced spermatogenesis complications in the murine model.