The purpose of this study to conform the effect of the aseptic dressing method to prevent infusion phlebitis. One quaxi-experimental, nonequvalent control group post-test design was used to evaluate prevention of phlebitis between a control group and an experimental group. The data for the control group were collected from 100 hospitalized patients from July 1 to November 30, 1999. The data for the experimental group were collected from 100 hospitalized patients from December 1, 1999 to March 5, 2000. The control group used paper tape on the IV site and the experimental group used a sterile gauze dressing which was changed every 24 hours. Two sets of instruments were used for this study. First, instrument developed Weinstein(1993) and modified by the researcher was used for judging phlebitis. The second, instrument developed Park(1996) was used for assessment records concerning the phlebitis which developed. Catheter sites were inspected on a daily basis by unit nurses and development of phlebitis was grade and documented. Data were analyzed using $x^2-test$ and stepwise regression The results are summarized as follows : 1. The incidence of phlebitis according to the duration of catheter insertion decreased in the experimental group($x^2=3.56$, p<.05). 2. The incidence of phlebitis according to the duration of catheter insertion decreased in the experimental group($x^2=28.79$, P<.0001). 3. No significant difference was found between the experimental and control groups in the severity of phlebitis. 4. A statistically significant difference between the two groups was found in the incidence of phlebitis according to the location of the insertion site. 5. No statistically significant difference between two groups was found in the incidence of phlebitis by age 6. A statistically significant difference between two groups was found in the incidence of phlebitis by sex($x^2=3.88$, p<.05) 7. Further study revealed that the duration of catheter and sex were predictors of occurrence of the phlebitis, explaining 38.2%, 14.2% of the total variance respectively. In conclusion, the aseptic dressing method is recommended to be prevent infusion phlebitis.