Objectives: to evaluate the serum level of 3 alpha diol G in patients with Acne Vulgaris (AV).  Background : AV is a clinical sign of Cutaneous Hyperandrogenism (CHA), one of the most frequent endocrine disorders in women of reproductive age .Women referred to the endocrine clinics for skin sym ptoms of hyperandrogenism (HA) should undergo laboratory work up; to evaluate hormone measurments and receive anti androgen therapy. Materials and methods: This study included 20 female patients  with AV presented to the Outpatient Clinic of Dermatology and Andrology Department of Benha University Hospitals between March 2021 and September 2021 and 20 healthy female volunteers were included in this study. The serum 3 alpha diol G was measured by ELISA method. Results: The current findings confirmed that there was statistically significant difference between patient group and control group as regard to the 3 alpha diol G levels. Conclusion: The 3 alpha diol G may have arole in the etiopathogenesis of AV.