Background: Hirsutism in females is defined as the presence of an androgen-dependent pattern of profuse terminal hair. The specific effect of Omentin-1 on hair development is not yet established. Omentin-1, on the other hand, has the potential to stimulate hair growth by either causing vasodilation or activating phosphatidylinositol 3-kinase (PI3K). Objective: This study aimed to evaluate serum level of omentin-1 in hirsute females in comparison with normal non hirsute. Patients and methods: This study included 42 females with hirsutism (21 idiopathic, 21 with polycystic ovary syndrome (PCOS) and 42 healthy matched controls. The included patients were chosen randomly from the Laser Unit in Dermatology Department of Mansoura University Hospital's. All patients were subjected to history taking, dermatological and gynecological examination, diagnosis of hirsutism, diagnosis of PCO, hormonal profile, assessment of serum omentin level. Results: Hirsutism with PCO subgroup showed significantly lower dehydroepiandrosterone sulphate (DHEA-S), significantly higher testosterone (TT), fasting blood glucose (FBG), fasting insulin, HOMA-IR when compared to those with idiopathic hirsutism subgroup (p < 0.001 for each). Higher omentin-1 level was significantly associated with idiopathic hirsutism when compared to hirsutism with PCO subgroups (mean= 309.7 versus 184.6, p < 0.001). Detection of omentin-1 level could be used as reliable indicator in discrimination between idiopathic hirsutism and those with PCO subgroups (AUC=0.912) with high sensitivity (95.2%) and specificity (95.2%). Conclusion: In females with idiopathic hirsutism, serum omentin-1 is increased, and this rise may contribute to excessive hair growth.