〔Abstract〕 Objective To explore the clinical characteristics and prognostic factors of the primary gastrointestinal mantle cell lymphoma(PGIMCL). Methods With the SEER database, clinical treatment information of PGIMCL patients from 1983 to 2015 was collected. Kaplan-Meier function was used to draw the overall survival(OS) and cause-specific survival(CSS) curves, then univariate and multivariate Cox regression analysis was used to evaluate the influence of various clinical factors on the prognosis. Results A total of 420 patients were subsumed into this case, most of them were elderly men, and the primary site was mostly in the intestine. Old age(OS:HR=2.210, 95%CI1.646-2.968,P<0.001; CSS:HR=2.024, 95%CI1.437-2.852,P<0.001), Ⅲ/Ⅳ stage(OS:HR=1.397, 95%CI1.065-1.833,P=0.016; CSS:HR=1.935, 95%CI1.391-2.692,P<0.001), the primary site was in the stomach(OS:HR=1.599, 95%CI1.205-2.121,P=0.001; CSS:HR=1.516, 95%CI1.079-2.130,P=0.017) patients with PGIMCL had poor OS and CSS. Female OS was superior to male(HR=1.390, 95%CI1.013-1.908,P=0.041). Conclusion Age, primary site and clinical stage are independent risk factors for prognosis of PGIMCL patients.