Objectives : The purpose of this study is to examine the infection control practice and performance study on knowledge of dental hygienist between their knowledge and general characteristics. Methods : The subjects in this study are 305 dental hygienists who received local in-service education on December 10, 2011 and February 28, 2012. Results : The infection prevention knowledge and performance are higher as work experience is more (p<.05), as the education level is higher and when they have undergone in-service education (p<.001). Also these are higher when they are working in the dentist at the present (p<.001). The infection prevention practice are different with respect to ages (p<.01), work experience (p<.001), and the highest level of education (p<.01). There are correlations between the infection control practices and knowledge, performance and knowledge. As the practice level is higher, it is shown that the performance is higher (r=.049, p=.01). Conclusions : It would be necessary to develop the systematic and continuous program in infection control education and to build system which makes in-service training for dental hygienists mandatory. These could improve the level of infection prevention knowledge, practice and performance of dental hygienists to prevent the exposure to infection of the people.