Objective We observed the effect of topical application of mucopolyccharide polysulfate cream (hirudoid) on phlebitis prevention initiated by continuous infusion of 5-Fu with Baxter infusor. Methods 60 untreated patients with nasopharyngeal carcinoma were selected and randomly divided into the control group (28 patients) and the experimental group (32 patients). The patients of the experimental group were gently massaged with hirudoid along the infusion vein since the beginning of 5-Fu infusion, while the control group received no intervention. The incidence of phlebitis was observed in the two groups. Results The incidence of phlebitis in the experimental group was lower and the degree was lighter compared with the control group. Conclusions Hirudoid can decrease the incidence and released the symptoms of phlebitis initiated by continuous infusion of 5-Fu with Baxter infusor, and is effective to prevent and treat phlebitis.