Liver status in 29 psoriatic patients, eight before methotrexate treatment and 21 after methotrexate therapy (three weeks to ten years), was evaluated by performing routine liver function tests, a test for sulfobromophthalein (Bromsulphalein) (BSP) retention, and liver biopsy. Results from liver function tests were normal in all but four patients but the BSP retention was elevated above 6% in ten patients. Among 21 patients treated with methotrexate, liver specimens from 16 showed fatty metamorphosis; from four, focal necrosis. Three of the patients treated with methotrexate, two of whom were heavy alcohol consumers, demonstrated portal fibrosis or cirrhosis. Of the control patients who had not received methotrexate, half had abnormal liver biopsy findings, which suggested that the overall evaluation of methotrexate damage to the liver will be complicated. Presence or absence of other liver disease, or history of exposure to potential hepatotoxins such as alcohol must be considered in evaluating patients for methotrexate therapy.