Objective To determine the role of hepcidin and related factors in evaluation of iron overload in patients with myelodysplastic syndromes (MDS). Methods Sixty-four patients with MDS were enrolled. The hepcidin levels in peripheral blood and bone marrow were measured by ELISA, the expression of growth differentiation factor 15 (GDF15) and twisted gastrulation 1 (TWSG1) mRNA was detected by Real-Time PCR, T lymphocyte subtypes (CD4+ and CD19+ lymphocytes) and T lymphocyte polarization were determined by flow cytometry, the deposition of iron in heart and liver was examined through magnetic resonance imaging T2* (MRI T2*), and serum ferritin (SF), C-reactive protein (CRP) and erythropoietin (EPO) levels were measured. Results There was no significant difference between hepcidin level in peripheral blood and that in bone marrow (P=0.134). Stratified according to WHO 2008 subtypes, the hepcidin level in patients with refractory anemia with ringed sideroblasts (RARS) was the lowest [（105.40±5.13）ng/mL], and that in patients with refractory anemia with excess blasts (RAEB) was the highest [（335.71±25.16）ng/mL], and there were significant differences among groups (P=0.041). Stratified according to IPSS and WPSS, there were significant differences in hepcidin levels between low-risk group and high-risk group in two systems respectively (P<0.05 and P<0.01). The SF level and expression of GDF15 mRNA in WPSS highrisk group were significantly higher than those in WPSS low-risk group (P<0.05), while there was no significant difference between IPSS low-risk group and IPSS high-risk group (P>0.05). Stratified according to T lymphocyte subtype and polarization, the hepcidin level in CD4+ high-expression group was higher than that in normal expression group (P<0.05), but there was no significant difference in the hepcidin levels between CD19+ high-expression group and normal expression group (P=0.206), and the hepcidin level in Th1/Th2>70.6 group was higher than that in Th1/Th2≤70.6 group (P<0.001). Stepwise regression analysis revealed that liver iron concentration (LIC, measured by MRI T2*), instead of SF and cardiac T2*, was correlated with hepcidin (r=0.582, P<0.001). Conclusion Inflammation has a significant impact on hepcidin expression, and the activation and polarization of T lymphocytes may partially participate in the mechanism. T2*MRI outperformed SP in evaluation of iron overload in patients with MDS.