Background PSMD7, a key member of the deubiquitinating enzyme family, plays a critical role in cancer development and progression. However, its role in laryngeal squamous cell carcinoma (LSCC) remains poorly understood. Objective To explore the clinical significance of deubiquitinating enzyme PSMD7 in LSCC, clarify its association with patient prognosis, analyze its immune infiltration characteristics and drug sensitivity, and verify the effect of PSMD7 on the biological functions of LSCC cells through in vitro cell experiments.Methods Data from the TCGA database were analyzed using R language for bioinformatics analyses, including differential expression analysis, survival analysis, enrichment analysis, immune infiltration analysis, and drug sensitivity analysis, to explore the impacts of PSMD7 on clinical prognosis, immune infiltration, and drug sensitivity in laryngeal cancer patients. In vitro experiments were performed using LSCC cell lines (AMC-HN-8 and FD-LSC-1). PSMD7 overexpression (OE-PSMD7), knockdown (si-PSMD7), and control (Control/si-NC) groups were established via plasmid transfection and siRNA technology. Quantitative real-time PCR (qPCR) and Western blot were used to detect PSMD7 expression in LSCC cells. CCK-8 and colony formation assays were used to evaluate cell proliferation; Cell migration and invasion was assessed by Transwell and wound-healing assays; Western blot was applied to analyze the expression of epithelial-mesenchymal transition (EMT)-related proteins (E-cadherin, N-cadherin, and vimentin).Results Differential expression analysis revealed that PSMD7 was significantly upregulated in laryngeal cancer tissues (P < 0.001). Survival analysis showed that patients with high PSMD7 expression had a significantly shorter overall survival (OS) than those with low expression (P < 0.001), and PSMD7 expression was correlated with clinical stage and T stage in LSCC patients. Enrichment analysis indicated that PSMD7 influenced the malignant progression of LSCC through signaling pathways including ATM. Immune infiltration analysis demonstrated positive correlations between PSMD7 expression and Th2 cells, eosinophils, and macrophages, while negative correlations were observed with B cells and CD8+ T cells. Drug sensitivity analysis further showed associations between PSMD7 expression and sensitivity to chemotherapeutic agents such as dabrafenib and rapamycin.In vitro functional experiments revealed that PSMD7 promoted LSCC cell proliferation (P < 0.05), migration (P < 0.05), and invasion (P < 0.05). Western blot analysis showed that PSMD7 regulated the expression of epithelial-mesenchymal transition (EMT) -related proteins (E-cadherin, N-cadherin, vimentin), thereby facilitating EMT in laryngeal squamous cell carcinoma cells. Conclusion The expression level of the deubiquitinating enzyme PSMD7 is closely related to the prognosis of patients, the characteristics of tumor immune infiltration, the selection of chemotherapeutic drugs, and their efficacy. It can affect the proliferation, migration, invasion, and EMT of laryngeal squamous cell carcinoma.