PURPOSE: The purpose of this study was to determine handwashing-related factors in nurses. Specific purposes of this study were to examine 1) the applicability of the hypothetical model constructed for this study, on the basis of Theory of Planned Behavior(TPB), and 2) relationships between handwashing practice and other variables such as age, career, level of education, and level of recognition about handwashing. METHOD: Data were collected from 187 nurses in one university hospital in Kyung-Ki province. RESULT: The hypothetical model based on TPB was revealed applicable, but the degree of the variance explaining handwashing practice was small(26%). Perceived behavioral control(PBC) was the most strong variable explaining handwashing practice, and intention didn't have a significant effect on handwashing practice. Norm and PBC had significant effects on intention, but attitude was not a significant factor of intention. Age, career, and the level of awareness of handwashing practice were significantly related to handwashing practice. CONCLUSION: The result of this study suggests that we should focus on perceived behavioral control, awareness of handwashing practice and subjective norm about handwashing practice to increase the level of nurses' handwashing practice.