Glycoprotein non-metastatic protein B (GPNMB) is a transmembrane glycoprotein that is highly expressed in several malignancies compared with its expression in matched healthy tissues. The aim of this study was to investigate the clinical characteristics and prognostic value of GPNMB expression in tumor tissue derived from a cohort of patients with head and neck squamous cell carcinoma (HNSCC). GPNMB expression in human HNSCC, oral dysplasia and normal mucosal tissue was evaluated by immunohistochemistry (IHC). The correlations of GPNMB expression with the clinical characteristics of HNSCC were assessed by one-way ANOVA and t test analyses. Survival data were analyzed using Kaplan-Meier analysis and the Cox proportional hazards model. GPNMB was highly expressed in HNSCC tissue compared with dysplasia and normal mucosal tissue. Additionally, a high level of GPNMB expression in HNSCC was associated with poor prognosis (P<0.01). In the analysis of tumor-node-metastasis (TNM) staging, a high GPNMB expression level in HNSCC tissue, as well as metastatic lymph node tissue, correlated with an advanced N stage. In conclusion, GPNMB was overexpressed in human HNSCC tissue and predicted poor prognosis in human HNSCC tissue. In addition, GPNMB expression was closely correlated with N stage in patients with HNSCC.