INTRODUCTION: Vitamin D deficiency is a common situation for women who are in menopause due to various reasons. This study aims to investigate the effect of VDR gene polymorphisms and lifestyle on vitamin D levels of women in menopause. METHODS: The study was planned in a cross-sectional descriptive design. Data was collected with a sociodemographic and lifestyle habits question form, and patients’ blood samples were obtained for vitamin D levels and genetic tests. The data was evaluated by using SPSS 16.0 software. The logistic regression analysis model was created using the Backward elimination method, and the P-value below 0.05 was considered statistically significant. Results: The study was carried out on 303 menopausal women. The frequency of vitamin D deficiency in patients was 71.9%. Receiving vitamin D and Omega-3 supplements and having prolonged sleep duration were found to be protective factors from vitamin D deficiency. Of the VDR gene polymorphisms, the Bsml bb genotype was found to protect from vitamin D insufficiency, while the ApaI bb genotype increased the risk of vitamin D insufficiency. DISCUSSION AND CONCLUSION: Vitamin D levels may be low in people who do not have sufficient sleep time. Our study found that the APA I aa genotype increased the risk of vitamin D deficiency, while the BsmI bb genotype protected from vitamin D deficiency. More studies are needed on the effects of lifestyle habits and genetic factors on serum vitamin D levels.