The pathogenesis of frontal fibrosing alopecia (FFA) is still unknown while hormonal factors have been postulated to play a role. There is scarce evidence with divergent results on the role of sex hormones in FFA. To evaluate the possible association between sex hormone levels and FFA, this study included 30 female cases of FFA and 34 healthy controls. Serum free testosterone, dehydroepiandrosterone sulfate (DHEAS), Luteinizing hormone (LH), follicle-stimulating hormone (FSH), 17-OH progesterone, androstenedione, and prolactin levels were measured in all subjects. Median and interquartile ranges of DHEAS and androstenedione were 79.26 (52.91-195.50) and 1.41 (0.90-2.29) in patients and 152.34 (81.72-218.63) and 2.31 (1.54-2.84) in healthy controls, respectively. The serum levels of DHEAS and androstenedione were significantly lower in FFA patients in comparison with healthy controls (P-value = .038 and .012, respectively). There were no significant differences in serum levels of free testosterone, LH, FSH, 17-OH progesterone, and prolactin between the FFA group and the control group The lower serum levels of DHEAS and androstenedione in FFA patients compared to controls is supporting a new growing concept of the low androgen level theory in the pathogenesis FFA, while the exact mechanism, clinical significance, and also the potential therapeutic effects of these hormones in FFA remain to be determined in future studies. K E Y W O R D S dehydroepiandrosterone sulfate, frontal fibrosing alopecia, sex hormones 1 | INTRODUCTION Frontal fibrosing alopecia (FFA) is a form of primary lymphocytic cicatricial alopecia with a distinctive clinical pattern of the frontotemporal hairline recession and eyebrow loss. 1,2 FFA is considered a variant of lichen planopilaris (LPP) which like LPP the infundibulo isthmic (bulge) region of the hair follicles is attacked by T-lymphocytic dominant inflammatory infiltrates. 1 In FFA, preferentially vellus like hairs are involved and permanently replaced by a scar-like fibrous tissue. 1 Although autoimmune, genetic, environmental, and hormonal factors have been proposed, the etiopathogenesis of FFA remains to be elucidated. The role of hormonal factors in the disease pathogenesis has been postulated based on the high prevalence of FFA in postmenopausal women, the association with early menopause, and androgenic alopecia 2 in some patients and the response to 5α reductase inhibitors. 3 In a multicenter study on 355 cases, Vañó-Galván et al found a high rate of women with FFA is presenting with early menopause or having undergone hysterectomy. 2 Ranasinghe et al in a retrospective study of 168 patients with LPP found androgen deficiency to be prevalent in many patients with FFA subtype. 4 In a case-control study on hormonal Soheila Nasiri and Sahar Dadkhahfar contributed equally to this study.