Peritoneal inclusion cysts are an important and underrecognized cause of benign pelvic and abdominal masses in post‐menopausal patients. Diffuse peritoneal cysts in this population can be difficult to distinguish from disseminated gynecologic malignancy on imaging and laboratory evaluation and will often be managed by gynecologists and gynecologic oncologists. Preoperative diagnosis may be suspected in the setting of findings of thin‐walled cystic lesions on imaging with indicative surgical or clinical history; however, given the risk of malignancy in this population, tissue diagnosis is necessary to exclude more serious diagnoses. Once the diagnosis of peritoneal inclusion cysts has been made, both diagnostic biopsy and complete resection of disease are reasonable treatment strategies, depending on patient goals and symptoms. There is no evidence supporting adjuvant therapy in the treatment or prevention of recurrence of peritoneal inclusion cysts in the post‐menopausal population. We present two cases that demonstrate these diagnostic and treatment principles for the gynecologic audience and summarize the existing evidence base for management these lesions.