Aim To explore the association between FOXP1, BCL2, and BCL6 gene expression in diffuse large B-cell lymphoma tumor cells and their association with the presence of FOXP3 lymphocytes. Methods Samples of lymph nodes from 53 patients with newly diagnosed diffuse large B-cell lymphoma were taken at the time of the diagnosis and immunostained for CD10, MUM1, BCL6, BCL2, FOXP1, and FOXP3. Fluorescent in situ hybridization analysis was used for the detection of FOXP1, BCL2, and BCL6 gene abnormalities. The χ2 test was used for data analysis. Results FOXP1 protein was detected in 28 cases, genetic abnormalities involving the FOXP1 locus were found in 19 cases, and both were present in 13 cases (χ2 =7.157; P = 0.028). FOXP3 positive cells were detected in 37 cases. There was a significant relationship between BCL2 expression and FOXP1 genetic abnormalities (χ2 =5.858; P = 0.016) and between BCL2 expression and BCL2 genetic abnormalities (χ2=6.349; P = 0.012). There was also an association between BCL6 and FOXP1 genetic abnormalities (χ2 =8.497; P = 0.004). Conclusion Association was observed between additional FOXP1 gene copies and BCL2 protein expression as well as changes on both FOXP1 and BCL2 genes in samples of our DLBCL patients.. FOXP3 positive cells showed no association with presence of any of analyzed proteins considered as a prognostic markers in DLBCL neither with changes of their genes.