Objective: Head and neck squamous cell carcinoma (HNSCC) is one of the world's eight most common malignancies and a severe hazard to human health. Transmembrane protein 208 (TMEM208) has been reported to be associated with autophagy,which is strongly tied to the onset and development of numerous illnesses, including cancer. For this reason, we investigated the expression and prognostic significance of TMEM208 in HNSCC. Methods: To explore the role and molecular mechanism of this gene in HNSCC, we performed a comprehensive analysis of the TMEM208 gene, including gene expression analysis, prognostic analysis, and immune infiltration analysis using the UALCAN, HPA, CVCDAP, DAVID, TIMER, CIBERSORTx, TISIDB, and cBioPortal online databases. It was further validated by in vitro cell culture. Results: Analysis of TCGA data showed that TMEM208 was highly expressed in HNSCC (P < 0.01) and significantly correlated with several clinicopathologic features, and in vitro cellular assays demonstrated that TMEM208 was highly expressed in multiple squamous carcinoma cell lines. Survival analysis showed that high expression of TMEM208 decreased OS (P=0.0088), PFI (P=0.0062), and DSS (P=0.0036) in HNSCC patients. cox regression analysis indicated that high expression of TMEM208 was an independent risk factor for OS in HNSCC patients (P<0.05). In addition, functional enrichment analysis showed that TMEM208 was closely associated with translation, ribosomal and mitochondrial functions, and GSVA analysis showed that TMEM208 was negatively correlated with a variety of immune cell differentiation in HNSCC, with a statistically significant difference. Immunocorrelation analysis showed that TMEM208 could affect immune cell infiltration in HNSCC; in addition, TMEM208 correlated with CD24, CD276, LAG3, and HVEM. Conclusion: In conclusion, TMEM208 holds promise as a prognostic indicator for HNSCC and is closely related to ICI treatment.