We describe two cases of strumal carcinoid of ovary, which is an extremely rare ovarian germ cell tumor composed of an intimate mixture of thyroid and carcinoid tissues. The first case involved a 63-year-old woman, who presented with a 1-month history of abdominal distension and unintentional weight loss (5 kg). Abdominal and chest computed tomography revealed right ovarian tumor and bilateral pleural effusion. Her thyroid-stimulating hormone level was slightly lower 0.475 μIU/mL (normal range: 0.55 -4.78 μIU/mL); however, the levels of FT3 and FT4 were normal. Intraoperatively, the right ovary was enlarged (8.0 cm × 7.0 cm), with a smooth surface and intact capsule. Bilateral salpingo-oophorectomy with a total abdominal hysterectomy and an appendectomy was performed. The second case was a 54-year-old woman, in whom pelvic mass was recognized 2 months before. Intraoperatively, the left ovary was dumbbell-shaped (20.0 cm × 9.0 cm × 9.0 cm) and connected to two masses (9.0 cm × 8.0 cm and 8.0 cm × 7.0 cm, respectively). Her thyroid function test was normal (0.70 μIU/mL). Total abdominal hysterectomy, partial omentectomy, and pelvic adhesion lysis were performed. In both patients, intraoperative frozen section suggested strumal carcinoid of the ovary (stage IA). Ovarian strumal carcinoid should be included in a differential diagnosis of adnexal masses. The prognosis is considered good.