In the carer guidance and the career counseling, there was focused on the cognition and the attitude, not focused on the career preparation behavior. So the purpose of this study is to develop and to validate the instrument for assessing the career preparation behavior of the Korean highschool students. The subjects of this study consisted of 255 highschool students and 42 college students. They listed the career preparation behavior which they have done, which they doing and will be done about the occupation and the career. In this process 54 items were driven. And career preparation scale which was composed of 39 items was made. In the second steps, total 403 highschool students have been participated. The exploratory factor analysis was executed. Career preparation behavior scale was composed of the 4 variables and 22 items. ① Collecting job information behavior(10 items), ② Occupation?major decision behavior(5 items), ③ Job experience behavior(5 items), ④ Employment preparation behavior(2 items), and it's item inter consistency, Cronbach's alpha coefficient was 0.89. The career preparation behavior scale which is composed of exploring career paths, collecting job information, doing job experiences, doing employment preparation is to executed systematically for helping the highschool students.