Objective:To investigate the characteristics of LDH5 expression in tongue squamous cell carcinoma (TSCC) and its relationship with clinicopathological parameters and survival. Methods:The LDH5 protein expression in 63 cases of TSCC and 16 cases of normal tongue mucosa were examined by immunohistochemistry. Based on these patients’ information and their follow-up data,the correlation of LDH5 expression with patients’ clinicopathological characteristics and overall survival were further evaluated by SPSS17.0 software using Fisher exact test and Kaplan-Meier method,respectively. Results:The LDH5 expression in TSCC (33/63,52.38%) was much higher than that in normal tongue (P < 0.001). LDH5 over-expression was found to be associated with tumor size,cervical lymph node metastasis and clinical stages (P < 0.05),but not with gender,age,local invasion and pathological grades(P > 0.05). The overall survival rate in patients with high LDH5 expression was significantly lower than that in patients with low expression as estimated by Kaplan-Meier and Log-rank test(P = 0.006). Conclusion:LDH5 is aberrantly over-expressed in a significant fraction of TSCC patients. Its upregulation is associated with multiple clinicopathological features and patients’ prognosis.