Objectives: To study the expression and significance of cyclinD2 and Bcl-2 in diffuse large B-cell lymphoma. Methods: This project used immunohistochemical methods to detect the expression of cyclinD2 and Bcl-2 in 120 cases of diffuse large B-cell lymphoma and 80 cases of reactive hyperplasia of lymphoid tissue. The materials were collected from the hospital from January 2018 to 2020. In March 2015, 120 patients had lymphoma tissue removed during the month of surgery. The postoperative pathological diagnosis was DLBCL. Another 80 cases of lymphoid hyperplasia (RLH) tissues were selected as controls. Results: CyclinD2 and BCL-2 expression were not statistically different in patients with diffuse large B-cell lymphoma in different ages, genders, locations, tissue types, and degree of differentiation; but statistically significant in different Ann Arbor stages, immunotypes, IPI index and first treatment efficacy. Conclusion: This research not only has important theoretical value, but also important economic value and social significance.