Background & aim: Menopause is accompanied with many problems such as coital discomfort, reduction of endometrial thickness and an increase in pH. Vitamin D is effective on proliferation and repair of epithelial tissue. Therefore, this study was conducted to determine the effect of vitamin D on vaginal atrophy among menopause women. Methods: In the present double-blind clinical trial study, forty-four women were randomly divieded into two groups. Treatment group received the vitamin D vaginal suppository, and the control group received placebo vaginal suppository in an 8 week period. Dyspareunia was assessed in first, 2, 4 and 8 weeks visit. The mean of Ph and maturation index of superficial cells were measured in the begnning of the study and at the end of the eighth week. The mann-whitney test was used for data analysis. Results: The mean of superficial cells and vaginal pH in the treatment group were (69.76±12.4) (1.42±.67) respectively while these figures were 54.66±18.38 and 2.9±0.73 for the control group.. The mean of sexual pain decreased considerably in the treatment group. Conclusion: Vitamin D is effective in maturation index and decreased pH and dyspareunia in menopause women.