Abstract： Objective To investigate the protein and gene expression of bcl-2, bcl-6 in diffuse large B-cell lymphoma (DLBCL). Methods 73 cases of DLBCL were selected for study using the Envision immunohistochemistry method with a panel of antibodies CD3, CD10, CD20, bcl-6, bcl-2, MUM-1. The bcl-2gene expression in 57 of 73 cases with chromosome translocation t (14; 18), breakage and amplification of 3q27 chromosome in 54 of 73 cases were detected by fluorescence in situ hybridization (FISH) method. Results The percentages of tumor cells expressing CD10, bcl-6, MUM-1, bcl-2 were separately 15.1%, 38.4 %, 71.2 %, 79.2 %. t (14;18) chromosomes were detected in 16 of 57 cases (28.1%). The expression of bcl-2 protein have significantly correlated with immunophenotype subtype (P=0.035), and t (14;18) was significantly correlated with the prognosis (P=0.045). There were no association between the expression of bcl-2 protein and t (14;18)(P=0.710). 11 of 54 cases were presented with 3q27 chromosomal breakage (20.4 %), and 14 cases were chromosomal amplification (25.9 %). The prognosis of cases with positive bcl-6 protein was better than that with negative protein obviously. There was no relationship between bcl-6 and 3q27 chromosomal breakage or amplification (P=1.000). Conclusion The expression of bcl-2, bcl-6 protein and gene were different events and had the different significance on DLBCL. The expression of bcl-2 protein was a prognostic marker correlated with immunophenotype subtype, and GCB type with the positive expression of bcl-2 protein had the poor prognosis. Conversely, t(14;18) was an independent event for the prognosis, and the positive expression have the poor prognosis. Patients who require the target therapy should be detected for the t(14;18). The expression of bcl-6 protein was beneficial to the judgment of DLBCL prognosis, it could be an independent factor of the prognosis. 3q27 chromosomal breakage may be a hint to the poor prognosis.