Aim To investigate clinical and diagnostic features of patients with external genital (retrocervical) endometriosis (RCE). Material and methods The study comprised 44 patients with RCE, who were examined and underwent surgery at the V.I. Kulakov NMRC for OGP from October 2016 to December 2017. Patients were divided into four subgroups. Baseline diagnostic work-up included gynecological and somatic history and diagnostic imaging (transvaginal ultrasound (TVUS), pelvic magnetic resonance imaging (MRI), and colonoscopy). All patients underwent laparoscopic surgery. The type of surgery was chosen based on location, the depth of invasion in the affected organs, the degree of spread in the rectovaginal space, and co-occurrence of colon endometriosis. Results The main clinical manifestations of RCE included pelvic pain, dysmenorrhea, dyspareunia, infertility, and dyschezia. The absence or presence of the endometriotic infiltration of retrocervical adipose tissue, found during the bimanual and rectovaginal examination, does not rule out infiltrating rectosigmoid endometriosis. Pelvic MRI complements ultrasound clarifying the location and extent of the endomeriotic lesion, and involvement of the pelvic organs in the pathological process. Bloating, mucus in stool, dyschezia during menstruation, ultrasound, and MRI findings suggestive of colorectal endometriosis, warrant a colonoscopy. The intraoperative findings complement and refine the data obtained during the pre-operative diagnostic work-up. Conclusion Patients with RCE need comprehensive diagnostic evaluation with laparoscopy as the final stage, excision of endometriotic lesions, and histological confirmation of the diagnosis.