Objective To analyze the expression level of miRNA-154 in cutaneous squamous cell carcinoma (CSCC) and its clinical significance in the development of CSCC.Methods RT-PCR and in situ hybridization were used to detect the expression of miRNA-154 in 98 cases of CSCC and 60 cases of normal skin. All the patients were followed up for 5 years, and the survival rate of the patients were counted and summarized. The relationship between the expression level of miRNA-154 and the prognosis of CSCC patients was further analyzed.Results The relative expression of miRNA-154 in CSCC tissues (0.57±0.09) was significantly lower than in normal tissues (1.56±0.02) (P<0.001). The average optical density of miRNA-154 expression in CSCC tissues (63.26±10.08) was significantly lower than in normal tissues (109.56±30.05) (P<0.001). The lower the level of miRNA-154 expression was in CSCC tissues, the higher the clinical stage, the lower the tumor differentiation, and the more prone to lymphatic metastasis (P<0.05). The overall survival rate of patients with high expression of miRNA-154 was significantly higher than that of patients with low expression of miRNA-154 (41.9 months vs. 31.4 months, P<0.001). Cox regression analysis showed that the low expression of miRNA-154, low tumor differentiation, high clinical stage, and lymphatic metastasis were related to the prognosis of death in patients with CSCC (P<0.05).Conclusion miRNA-154 is an important tumor suppressor gene in the occurrence and development of CSCC. The expression of miRNA-154 showed a negative relationship with tumor differentiation, and a positive relationship with the clinical stage, lymphatic metastasis and survival rate of CSCC patients. miRNA-154 may be a potential target for anti-tumor biotherapy of CSCC.