Objective To investigate the characteristics of MSCT in the diagnosis of primary epiploic appendagitis(PEA), and to improve the understanding of the disease. Methods Clinical and radiographic data of 24 patients with CT from 2012 to 2016 were collected. The CT scans of the PEA were evaluated for location in relationship to the colon, size, a focal fatty center, the presence of colon wall thickening。And 5 patients with followup CT comparing with CT for the first time. Results The most common part of colon involved by PEA was the sigmoid colon, and the most common position was anterior to the colonic lumen. All lesions were round like fatty mass abutting the colon, the edge has a complete or incomplete annular soft tissue density, 13 cases of internal visible dot or small pieces of high density. 21 lesions adjacent visible peritoneal thickening of different level, colon wall thickening was present in only 2 cases. The lesion size, internal density and size of the internal high density sign were observed to change over time in the CT images of 5 patients with follow-up. Conclusion PEA has a certain clinical and imaging features. The most common finding on CT is a fat-density oval lesion with surrounding inflammation on the anterior aspect of the sigmoid colon. Review of CT lesions with time changes.