Endometriosis is a chronic inflammatory disease defined as the presence of endometrium-like tissue outside the uterus. It is mostly found in women of reproductive age.Depending on the involved site, women can present with various symptoms. We report a case of rare, atypical site of endometriosis - primary inguinal cutaneous endometriosis. A 27-year- old woman presented to our Department with a history of a painful, firm, movable, subcutaneous nodule 1 × 1 cm of size in the right inguinum. She experienced flares of pain with her menstrual cycle and dysmenorrhea. Ultrasound revealed hypoechoic nodule with vascular flow. Punch biopsy of the nodule was performed. The biopsy results showed adipocytes and cell inclusions partially positive on epithelial membrane antigen. After surgical excision of nodule with wide margins, tissue was consisted from endometrial glands with encompassing fibrotic stroma. No additional signs of endometriosis were found. Because the condition is rare and can mimic presentations of other diseases, such as lymphatic nodule, keloid, dermatofibroma protuberans, cutaneous metastasis of cancer or dermatofibroma, cutaneous endometriosis can be difficult to diagnose.