The clinical and histological and immunohistochemical characteristics were observed and analyzed. And the relevant literature of 3 cases of primary ovary carcinoid was reviewed. The onset age was 61, 34, and 73 years old respectively. Two patients mainly presented as solid or cystic-solid mass of ovary when made a physical examination and 1 patient was found to have a cystic-solid mass of ovary during caesarean section. The histological types were trabecular type, mainly trabecular type mixed with insular type, and strumal carcinoid with mature teratoma of ovary. Immunohistochemical staining results showed that 3 cases were positive for synaptophysin and CDX2, 2 cases were positive for chromogranin A, and 3 cases were negative for TTF-1. Thyroid area of strumal carcinoid was positive for TTF-1 and thyroglobulin. Primary ovary carcinoid belongs to low-grade neuroendocrine tumors, which has low potential malignancy and good prognosis. It should be differentiated from metastatic carcinoid, granulosa cell tumor, sertoli cell tumor, and thyroid papillary carcinoma of ovary and medullary thyroid carcinoma struma ovarii.