Two cases of simultaneous occurrence of myasthenia gravis (MG) and thymolipoma are described and 4 previously reported cases are reviewed. In all 6 cases, thymectomy was performed. Pre- and postoperatively, the clinical status of the patients was similar to that of late-onset MG without thymolipoma. It is possible that simultaneous occurrence of MG and thymolipoma may be coincidental.