Malignant acanthosis nigricans is very rare disease. The disease is related with internal malignancy, especially gastrointestinal tract malignancy. Reported occurrence rate of malignant acanthosis nigricans associated internal malignancies are 64% of stomach adenocarcinoma, 27% of other organs of abdomen (liver, gall bladder, small intestine, rectum, uterus, ovary), 9% of non-abdominal organs(breast, lung). We report a case of malignant acanthosis nigricans associated with stomach adenocarcinoma from 20-year-old female and discuss review of literature on a acanthosis nigricans briefly.