We treated 4 with a diagnosis of diffuse large B cell lymphoma involving the gastrointestinal tract with rituximab combined with adjusted dose EPOCH (R-DA-EPOCH) scheme based on a comprehensive analysis of the onset process, clinical and pathological features, and prognosis of the patients, and evaluated their treatment response. Complete remission (CR) was achieved in 3 patients after the treatment and 1 patient with diabetes and hypertension died due to severe infection. R-DA-EPOCH regimen as the first-line treatment of gastrointestinal diffuse large B cell lymphoma has a good short-term efficacy, but its long-term efficacy awaits further evaluation in future studies with larger sample sizes.