Abstract: Objective To study the relation between expression levels of cathepsin B and L as well as stefin A in peripheral blood of patients with laryngeal carcinoma and its diagnosis and prognosis. Methods Cathepsin B and L as well as stefin A levels in serum of 60 laryngeal carcinoma patients and 30 normal controls were measured by enzyme linked immunosorbent assay. Results The levels of cathpsin B and L were significantly higher in serum of laryngeal carcinoma patients than in normal controls（P＜0.01）.The expression levels of cathpsin B and L were positively correlated（r=0.4341,P＜0.05）.The stefin A level was significantly lower in serum of laryngeal carcinoma patients than in normal controls（P＜0.01） but not correlated with the levels of cathpsin B and L. Conclusion High cathpsin B and L level of and low stefin A level in serum of laryngeal carcinoma patients contribute to the diagnosis of laryngeal carcinoma and judgment of its prognosis.