A colon cancer presenting as psoas muscle abscess is very rare. A 27-year-old woman was admitted with abdominal pain, fever, and discomfort on left thigh. She had been administered on anti-tuberculosis medication for colonic tuberculosis since 3 months ago. Abdominal CT scan revealed a mass lesion obstructing the descending colon with an abscess formation within left psoas muscle. We undertook segmental resection of obstructing descending colon after the percutaneous drainage of psoas abscess. The pathologic report was mucinous adenocarcinoma of the colon. We report the first case of colon cancer manifested with psoas abscess in Korea, with the review of literature associated with the correlation of colon cancer and tuberculosis.