Studies have suggested an association between pretransplant serum levels of ferritin and C-reactive protein (CRP) and complications of allogeneic hematopoietic stem cell transplantation (HSCT). To evaluate the prognostic impact of these biomarkers on the development of acute and chronic graft-versus-host disease (GVHD), we retrospectively studied 211 patients who underwent allogeneic HSCT for hematologic diseases at our institution. The cumulative incidence rate of chronic GVHD at 3 years was 40.7 %. In the multivariate analysis, elevated CRP levels (≥2 mg/L) were significantly associated with a high incidence of chronic GVHD, whereas high ferritin levels (≥880 ng/mL) showed a tendency, though not statistically significant, to association with a low incidence of chronic GVHD. No significant association was observed between the pretransplant serum ferritin or CRP levels and the incidence of acute GVHD. Multivariate analysis indicated that high pretransplant serum ferritin levels were significantly associated with increases in treatment-related mortality and relapse rates. Overall, an elevated pretransplant serum ferritin level, but not an elevated serum CRP level, is a strong risk factor for overall mortality (hazard ratio, 2.16; P = 0.002). Our results also indicate that pretransplant serum CRP levels may be a useful biomarker for predicting the risk of chronic GVHD.