Direct immunofluorescence (DIF) of skin is the gold standard in the diagnosis of pemphigus vulgaris (PV). Since the outer root sheath (ORS) of hair follicle is structurally analogus to epidermal keratinocytes, both of them show similar DIF pattern. So DIF of hair may be an alternate substrate for monitoring disease activity of PV. Our objectives were to see effectiveness of ORS as an alternate reliable substrate for DIF test in monitoring patient with pemphigus vulgaris. We found that DIF of hair is a simple, specific and noninvasive test, and provides the opportunity to avoid repeated skin biopsies as an appropriate substrate for DIF for the disease monitoring in patients with PV.