Multiple primary cancer is defined as the multiple occurrence of malignant neoplasms in the same individual. According to the development of new diagnostic techniques and the increase in long-term survivals, reports of multiple primary cancer have been gradually increasing among patients treated for initial cancers. Since Theodor Billroth reported the first three cases of multiple primary cancer in 1889, there have been many reports of multiple primary cancer, with an incidence range in Korea of 0.35~1.84%. In Korea, there have been a few reported cases of triple cancer. Herein, three recently experienced cases of metachronous triple primary cancer are reported.