Thymomas with ring calcifications are very rare and quaint style. Herein, we presented our three cases of thymomas with ring calcifications and reviewed totally 10 cases including 7 cases of previous English literatures. The median age was 53 years. Myasthenia gravis was a complication in 40%. The median maximal diameter was 50 mm. They were diagnosed as pathological type B or had type B component. Based on World Health Organization (WHO) classification, 20%, 60%, and 20% cases were stage I, stage II, and stage III, respectively. Seven ring calcifications were within tumors (inner type) and two cases were outside tumors (outer type). The other had a thymoma arising in the calcic wall of a calcified thymic cyst (miscellaneous type). Four other anterior mediastinal tumors with ring calcification had been reported. We need pathological examinations for a definitive diagnosis. Surgeons should plan surgery because of the possibility of invasive thymomas, or other malignant tumors.