Objective: To elucidate the expression and clinical significance of thymidine phosphorylase (TYMP) gene in clear cell renal cell carcinoma (CCRCC). Methods: Oncomine and GEPIA databases were used to analyze the expression of TYMP gene in normal kidney tissues and CCRCC tissues. The GEPIA database was used to analyze the relationship between the expression of TYMP gene and the pathological stage. The expression level of TYMP gene and survival rate of CCRCC patients were analyzed by Kaplan-Meier and log-rank test in OncoLnc database. The difference of DNA methylation level in TYMP promoter region between CCRCC tissue and normal kidney tissue was analyzed by MethHC database. The String-DB database was used to analyze the proteins with the TYMP protein. Finally, the expression of TYMP protein in normal kidney tissues and CCRCC tissues was analyzed by the Human Protein Atlas database. Results: At the mRNA and protein levels, TYMP was significantly higher in CCRCC tissues than that in normal kidney tissues, and the higher the expression level of TYMP mRNA, the higher the pathological stage of CCRCC. Compared with the low expression group of TYMP gene, the overall survival rate of patients with high expression of TYMP gene was significantly lower , the DNA methylation level of TYMP promoter region in CCRCC tissues was significantly lower than that in normal tissues . TYMP related proteins were TK2, NT5M, CDA, UPRT, NT5C, UPP2, UMPS, TK1, UPP1 and DPYD, which were involved in the synthesis, decomposition, metabolism, transfer of pentose groups, protein homopolymerization and other biological processes. Conclusion: Large sample data mining can quickly obtain the relevant information of TYMP gene expression in CCRCC tissues, which lays a foundation for further study on the mechanism and prognosis of TYMP gene in the development of CCRCC.