Abstract: Objective To investigate the characteristic 18F-FDG PET/CT findings in patients with primary intestinal lymphoma (PIL). Methods We collected the clinical and 18F-FDG PET/CT data of 23 patients with PIL who underwent 18F-FDG PET/CT in our center between January, 2005 and January, 2016. The location, morphologies and metabolic features of the lesions were analyzed in these patients. Results In the 23 PIL patients, diffusive large B cell lymphoma (DLBCL) and enteropathyassociated T cell lymphoma (EATL) were the primary histopathological types, accounting for 47.8% and 43.4% of the total patients, respectively. The ileum, ileocecus and ascending colon were the most commonly compromised locations (57.0%). All the 42 intestinal lesions showed 18F-FDG-avid foci with a mean SUVmax of 15.2±8.1 (range 3.6-33.7), and no significant difference was found in SUVmax between DLBCL and EATL groups (t=1.851, P=0.073). Diffusive regular or irregular intestinal wall thickening was the primary CT finding in PIL lesions without significant difference between the two groups (χ2=0.426, P= 0.514). The aneurismal sign was found in 26.2% (11/42) lesions, more commonly seen in the patients with DLBCL than in those with EATL (χ2=8.101, P=0.004). PET/CT detected abdominal lymph node involvement of lymphoma was detected in 56.5% of the patients, and a small quantity of asites was seen in 30.4% of the patients. Conclusion PIL presents with characteristic imaging features in 18F-FDG PET/CT. 18F-FDG PET/CT is a sensitive imaging modality for detecting inter- and extra-intestinal lesions of PIL and displays characteristic imaging features of the disease.