Abstract: Objective To investigate the difference of Id4 gene promoter methylation in patients with different subtypes of myelodysplastic syndrome（MDS）. Methods MS-PCR was used to detect the Id4 gene methylation in 56 patients with different subtypes of MDS.Id4 gene methylation was detected in bone marrow samples from healthy donors. Results No methylation of Id4 gene was found in bone marrow samples from healthy individuals.In subtype groups of MDS patients with a lower or higher ratio of blast cells than 5%,the incidence of Id4 gene methylation was different（P＜0.05）. Conclusion Id4 gene methylation can be found in MDS patients with a higher ratio of blast cells.