Objectives : The purpose of this study was to investigate the reproductive effect of Ginseng radix on male mice. Methods : Male C57BL/6J mice were divided into four groups ; normal group (vehicle-treated, n=8), Ginseng radix treatment group (100, 500, 1000 mg/kg, n=8). Ginseng radix extract was treated for 5 weeks. After treatment each group was examined for assessment of sperm count and CatSper protein expression using computer assisted semen analysis (CASA) system and the immunofluorescence. Results : Sperm count of normal and Ginseng radix extract treated group were 287.57 vs. 371.62, 364.83, $343.29{ imes}10^6$, respectively. The CatSper3, 4 proteins expression of Ginseng radix treated group were significantly increased than that of normal group. Conclusions : These findings suggest that the Ginseng radix improves male reproductive function by increasing sperm count and CatSper protein expression.