Abstract: Thymidine phosphorylase(TP) is an important enzyme in the pyrimidine nucleoside synthesis and decomposition.Based on current hypotheses, a homology between TP and platelet-derived endothelial cell growth factor is found.A close relationship was observed between the function of TP in inducing angiogenesis and the anti-apoptotic property as well as the progression and metastasis of colorectal carcinoma.TP is the key enzyme that can convert 5' deoxy-5-fluorouridine(5'-DFUR), one of the prodrugs of 5-fluorouracil(5-FU), into 5-FU.TP activity is strongly linked to the sensitivity and the targeted therapy of fluorouracil drug on colorectal carcinoma cells.Therefore, clarifying the expression mechanism is of great importance.This article summarized the function of TP in angiogenesis, TP expression in colorectal carcinoma, and 5'-DFUR activation in cells.Current research progress in colorectal carcinoma treatment was also described.