Sclerosing mesenteritis (SM) is a chronic nonspecific mesenteric inflammation. I report a case of a 72-year-old male treated with etanercept for psoriatic arthritis for 7 years who developed abdominal discomfort, urinary retention, acute kidney injury, and bilateral ureteric obstruction. CT abdomen revealed retroperitoneal mass. Biopsy showed sclerosing mesenteritis. One year later, after discontinuation of etanercept, CT abdomen showed regression of the mass. To my knowledge, this is first case report of reversible sclerosing mesenteritis associated with etanercept therapy.