Various biomarkers have been investigated with regard to their ability to predict the outcome of allogeneic hematopoietic SCT (HSCT). In this study, we retrospectively reviewed 90 recipients who received HSCT between 2007 and 2011 in our institution, and evaluated the predictive value of the baseline serum C-reactive protein (CRP) levels just before the initiation of conditioning for transplant-related complications after allogeneic HSCT. A receiver-operating characteristic curve revealed that the baseline serum CRP levels had an excellent predictive value for non-relapse mortality (NRM), with an area under the curve of 0.83. The sensitivity and specificity for NRM were 80% and 87%, respectively, with a cutoff of 0.6 mg/dL. With this cutoff value, multivariate analyses revealed that a higher baseline CRP level was an independent risk factor for NRM (HR 6.21, P<0.01), grade III-IV acute GVHD (HR 3.91, P=0.03) and poor overall survival (HR 3.27, P=0.0018). On the other hand, the baseline CRP level did not predict infectious events. These findings suggested that CRP levels before conditioning may be a useful predictive biomarker for poor survival.