Purpose : The purpose of this study was to identify the factors that influence the behavior of intensive care unit (ICU) nurses regarding radiation protection, and to provide basic data to improve radiation protection educational programs. Methods : This descriptive research study included 143 nurses working in ICUs. Data were collected through a self-reported structured questionnaire and analyzed using t-test, Pearson’s correlation coefficients, and hierarchical multiple regression analysis. Results : Radiation protection environment (<i>β</i>=.35, <i>p</i>=.001), radiation protection self-efficacy (<i>β</i>=.25, <i>p</i> =.002), type of hospital (<i>β</i>=-.25, <i>p</i>=.002) and experience in ICU (<i>β</i>=-.18, <i>p</i>= .022) affected the radiation protection behavior of ICU nurses. The total explanatory power of model was 60.0% (R<sup>2</sup>=.64, Adj. R<sub>2</sub>=.60, F=17.71, <i>p</i><.001). Conclusion : In order to enhance the standards of radiation protection behavior among intensive care unit nurses and improve radiation protection self-efficacy, educational and training programs should be developed. Additionally, administrative support should be considered to create environments with better radiation protection at the organizational level.