Here one concurrent case of a patient with both thyroid and breast cancers was discussed with a comprehensive literature review. On March 21, 2016, a 42-year-old female patient was admitted into our hospital because of right neck mass and left breast mass for 1 week during a routine health examination. On March 22, the combined procedures of complete resection of right thyroid gland plus isthmus with dissection of lymph nodes in right VI region plus left breast regional lumpectomy were performed under endotracheal anesthesia. Final diagnosis: Mammary cancer (right thyroid gland), PT1aN1aM0 (stage I); ductal breast cancer (left breast), PT1NxM0 (re-operation within two weeks). For either disease, a practicing clinician should stay on a high alert for individual and familial endocrine diseases. And breast molybdenum target imaging and type B ultrasound should be performed regularly for screening. It is always prudent to catch and treat diseases as early as possible. The conclusion is as follows.