Hematological malignancies (HM) are a group of neoplastic diseases that arise from hematologic cell lineages. Transforming growth factor beta 1 (TGFβ1) is shown to negatively regulate normal and malignant hematopoiesis and, in immunological context, to promote T cell exhaustion and generation of regulatory T cells, which are shown to be deleterious in cancer, by the induction of transcription factor FOXP3 expression. The present study aimed to evaluate TGFB1 exon-1 rs1800470 and FOXP3 intron-1 rs2232365 polymorphisms in relation to HM susceptibility. DNA was extracted from blood samples of 43 HM patients and 142 neoplasia-free individuals and polymorphisms were analyzed by allelic-specific PCR. Association analysis was assessed by the Odds Ratio (OR) with significance level of 5%. Regarding FOXP3 polymorphism, no significant differences were observed in genotype or allele distribution among the patients and controls. However, there was a positive association between TGFB1 TT genotype and HM susceptibility (OR = 4.07; CI95% = 1.94 - 8.52). In the combined analysis, a positive association was also observed for TGFB1 TT and FOXP3 GG genotypes (OR = 4.00; CI95% = 1.54 - 10.41) in relation to HM susceptibility. Our results indicated promising new markers to be further investigated in hematological malignancies.