Background: Splenic diffuse red pulp small B-cell lymphoma (SDRPSBCL) is rare and accounts for less than 1% of non-Hodgkin's lymphoma. As the first or accompanying symptoms of SDRPSBCL, gastrointestinal hemorrhage (GIH) is rather unusual. Patients and Methods: We reported on a patient with SDRPSBCL complicated with GIH. According to the enteroscopy, pathological sections of spleen and intestine, immunohistochemistry and other related laboratory examinations, the patient was diagnosed as SDRPSBCL (stage IVb) complicated with colon and rectal ulcers. The clinical manifestations were hematochezia, unformed stool, continuous anal pain and poor quality of life. Subsequently, the patient was treated by six cycles of CHOP (cyclophosphamide + doxorubicin + vincristine + hydroprednisone) regimens. The clinical features, diagnosis and treatment were analyzed retrospectively and the relevant literatures were reviewed. Results: After the first course of chemotherapy, the patient did not have any more bloody stool and the stool was shaped. After six cycles of chemotherapy, the patient's anus was no longer painful and he has been in complete remission according to the result of positron emission tomography CT. Conclusion: Through analysis of this case, we could elucidate that after the primary disease was alleviated, the bleeding degree of digestive tract was relieved, which provided the basis for the clinical treatment of this rare disease.