Background: Vitamin D deficiency is more common in peri-menopausal women than previously thought and it may impair quality of life mainly due to lack of awareness about the importance of vitamin D and prevention of its deficiency. Vitamin D deficiency is now being increasingly associated with non-classical roles, like linking it with autoimmune diseases as well as chronic diseases. The study was aimed to: assess perimenopausal women's perception regarding vitamin D deficiency. Research design: A Descriptive study design was used. Sample: A Purposive sample included 311 perimenopausal women who were obtained from gynecology outpatient clinic at Ain Shams University Maternal hospital. Tools: first tools, Structured interviewing questionnaire to assess perimenopausal women's general characteristic and their knowledge regarding vitamin D deficiency. Second tool, Lirket scale to assess perimenopausal women's attitude regarding vitamin D deficiency. Results: (80.4%) among the studied samples had satisfactory total knowledge score regarding vitamin D deficiency, while (19.6%) of them had unsatisfactory level and (30.8%) of the studied samples were received their knowledge from internet, while (25.6%) of them received their knowledge from health caregivers, while (91%) of them had a positive total attitude score toward vitamin D deficiency in addition to there was a positive correlation between studied sample's total knowledge score and studied sample's total attitude regarding vitamin D deficiency p<0.001. Conclusion: The majority of the studied samples had satisfactory total knowledge score regarding vitamin D deficiency while less than one fifth of them had unsatisfactory level, as well as the majority of the studied samples had a positive total attitude score toward vitamin D deficiency. Recommendations: Establish perimenopausal educational program to increase women health awareness about screening for vitamin D deficiency. Further research needed to study the effect of self-care guideline on perimenopausal women's screening regarding vitamin D deficiency