To evaluate the clinical significance of subcategory and severity of chronic graft-versus-host disease (GVHD) as defined by the National Institutes of Health (NIH) consensus criteria, we retrospectively studied 211 patients with hematologic neoplasms who survived beyond 100 days after allogeneic hematopoietic cell transplantation. Endpoints included chronic GVHD-specific survival (cGSS), duration of immunosuppressive treatment, and non-relapse mortality (NRM). A total of 96 patients fulfilled the NIH diagnostic criteria for cGVHD. In univariable analysis, patients with NIH overlap syndrome tended to exhibit lower cGSS compared to those with NIH classic cGVHD [hazard ratio (HR) = 2.76, P = 0.060], while patients with severe cGVHD at onset had a significantly lower cGSS compared to those with mild-to-moderate cGVHD (HR = 3.10, P = 0.034). The duration of immunosuppressive treatment was not significantly affected by either subcategory or severity of NIH cGVHD. In multivariable analysis treating cGVHD as a time-dependent covariate, development of overlap syndrome (HR = 3.90, P = 0.014) or severe cGVHD at peak worsening (HR = 6.21, P < 0.001) was significantly associated with higher risk of NRM compared to the absence of cGVHD. Our results suggest that both the subcategory and severity of NIH cGVHD are partly correlated with cGSS and may play a useful role in distinguishing patients at high risk for NRM, warranting validation of this approach through future prospective studies.