The purpose of this study was to analyze factors affecting unit chair surface management to prevent cross infection of dental hygienist. A total of 311 dental hygienists were surveyed and received general characteristics and responses to dental infection characteristics. The surface of the unit chair was divided into 5 parts and the items for each management method were examined. The statistical analysis of this study was carried out by correlation analysis and multiple regression analysis using SPSS. According to the results of the study, 94.3% of the dental hygienists responded that the infection was important and the related education experience was 76.2%. As for the unit chair management period, the most frequent response was to the start of treatment every day, with 46.6%. The management method was not using disposable cover or disinfectant. The factors influencing the unit chair management were the average number of patients per day, and the bracket table was related to the number of chairs. Control switches were found to be associated with the importance of infection control. In conclusion, although the awareness and practice of infection control is high, it is necessary to improve the method, and it seems that the management of unit chair is insufficient in dental hospitals with many patients and unit chairs. Policy improvement that can be dedicated to infection prevention activities seems to be very necessary.