Abstract: Objective To explore the clinicopathological characteristics, prognostic factors and effective treatment modalities of primary gastrointestinal diffuse large B-cell lymphoma (PGI-DLBCL). Methods A total of 52 PGI-DLBCL patients who were admitted to the Affiliated Hospital of Southwest Medical University from June 2013 to November 2021 were enrolled and their clinical data were retrospectively analyzed. The survival prognosis of 39 patients who could be followed up was analyzed. The Log-rank test was used for univariate analysis, while the Cox regression model was used for multi-factor analysis. Results Univariate analysis showed that LDH level, Lugano stage, whether the tumor involved multiple sites, IPI group and whether the lesion was completely resected were associated with the prognosis of PGI-DLBCL patients (P<0.05). Multi-factor Cox regression analysis showed that elevated LDH level, Lugano stage IIE-IV, IPI group and tumor involvement at multiple sites were the independent risk factors for the prognosis of PGI-DLBCL patients (P<0.05). Conclusions PGI-DLBCL patients with elevated LDH levels(＞250 U/L),Lugano stage ⅡE-ⅡV, poor IPI group and tumor involvement in multiple sites in the gastrointestinal tract have poor prognosis.