This study identified knowledge, attitudes and behavior for radiation safety managemen of career dental hygienists and new dental hygienists. Results obtained from this study are as follows. 1. Regarding the knowledge level of radiation safety management, average score was 8.25±2.47 for career dental hygienists and 7.42±2.77 for new dental hygienists from 15 scale test.(p<.001). In addition, knowledge level of radiation safety management by general characteristics showed statistically significant difference according to health status(p<0.01). 2. Regarding the attitude level of radiation safety management, average score was 4.35±0.55 for career dental hygienists and 4.19±0.60 for new dental hygienists from 5 scale test.(p<0.01). 3. Regarding the behavior level of radiation safety management, average score was 3.14±0.98 for career dental hygienists and 3.33±0.99 for new dental hygienists from 5 scale test.(p<0.05). In addition, the behavior level by general characteristics showed statistically significant difference according to attendance rate of radiation safety management training (p<0.01) and defences of clinic (p<.001). 4. Based on the survey of relationship among knowledge, attitude and behavior of radiation safety management, we found that the higher the knowledge level of radiation safety management was, the higher the level of attitude was(p<.001).