The primary purpose of this study is to suggest specific measures of restructuring high school curriculum and implementing strategies through the surveys and in-depth interviews with educational experts and high school teachers. Before conducting this survey, this research analyzed nine critical features of the high school credit system such as definition of the credit system, students’ choice of subjects, alternative subjects, minimum required credits, graduation criteria, and connecting university entrance, etc. The number of survey participants was 10,552 including teachers of pilot school for the high school credit system as well as ordinary high schools and educational experts. The survey revealed that participants requested decreasing required credits, implementing career intensive course, modifying the current graduation requirement based on school attendance, securing quality control of curriculum, providing measures for underachievers, and satisfying students’ needs for subjects and the quality. Through the analysis of the survey, this research suggests specific and effective policies about reducing the minimum number of credits with flexible curriculum, operating career-intensive programs with individual school’s decisions, and modifying criteria for passing, incomplete, retaking credits and graduation. Furthermore, this output suggests that securing students’ rights of selecting subjects and controlling quality of subjects are crucially important to implement the high school credit system.