Sclerosing mesenteritis is a rare disease of the mesentery. Associations with surgery, trauma, autoimmunity and paraneoplastic syndrome have been suggested, but most of the cases remain idiopathic. Diagnosis is often incidental, based upon the finding of a single or multiple mesenteric lesions on abdominal CT and histopathological confirmation. Optimal treatment is still controversial, but most of the cases reported have a favourable prognosis. We present a case of a 54-year-old male with long-standing abdominal pain and nausea, whose CT revealed the presence of a large mesenteric mass. A biopsy was performed, revealing benign chronic inflammation, fibrosis and IgG4-positive plasmocytes consistent with sclerosing mesenteritis. Clinical remission was achieved with corticosteroids and follow-up CTs at six and twelve months documented stability of the lesion. Furthermore, we review the current literature on the diagnosis and treatment options for this rare disease.