Before the advent of CT, disease processes of the mesentery were identified indirectly by displacement ofopacified bowel. Although ultrasound has proved to be useful in imaging mesenteric lesion, it has many limitationsin detecting pathologic change of adjacent mesentery, relationship between mesenteric lesions and surroundingorgans, but CT with its excellent depiction of cross-sectional anatomy gives good definition of mesentery anddiseases affecting mesentery. Authors analyzed CT freatures of pathologically or surgically proven mesentericdiseases for recent 2 years at Keimyung University Dongsan Medical Center. The results were as follows: 1. Of 42cases, 23 were male and 19 were female, and age ranged from 4 to 74 years old, most common in 7th decade. 2. Themost common mesenteric mass was lymphoma(14 cases: 33.3%) followed by primary mesenteric tumors(10 cases: 23.8%),abscess(6 cases:14.3%), tuberculosis(5 cases: 11.9%), metastasis(4 cases:9.5%) and hematoma(3 cases:7.2%). 3.Mesenteric cysts were defined, thin walled cystic masss with frequent internal septations. There was one case ofwall calcification. 4. In all cases of peritoneal mesothelioma, there were linear or granular infiltration onmesentery and omentum, accompained by ascites. Characteristic stellate pattern and pleated appearance of mesenterywas noted in 2 cases. 5. Mesenteric fibroma was round soft tissue mass of homogeneous attenuation. 6. Of 14 casesof lymphoma, 12 cases showed variable pattern of mesenteric mass: round(16 cases), cake-like(2 cases),ill-defined(1 case) mass and mixed pattern (3 cases). There wre diffuse mesenteric thickening without mesentericmass in 2 cases. 7. Mesenteric abscess revealed round cystic mass with irregular wall in 4 cases, and irregularlinear infiltrations and adjacent in all. And there were ill-defined mass of phlegmon in 2 cases. 8. Mesenterichematomas were cake-like mass in 1 case, and ill-defined triangular mass in two. Mean density were 60HU-70HU. 9.Three of 4 cases of metastatic mesenteric msses have large solid round masses, but one case shows stellate patternof mesentery. 10. Abdominal tuberculosis were ill-defined mass in 2 cses, and stellate pattern in two. One casewas mixed pattern. There were cental low density with rim enhancement in 2 cases of lymphadenopathy. 11. CT wasexcellent modality in detection of mesenteric lesion, and also useful in differential diagnosis of mesentericdisease by analysis of shape, size, extent, attenuation value, contrast enhancement pattern of the lesion andadjacent mesenteric change.