The purpose of this study is to investigate the duties of teachers working at secondary level technical vocational education institutes, and analyze job importance, difficulty and frequency of performance perceived by teachers. For deducing the duties of teachers working at secondary level technical vocational education institutes, they were theoretically devised by reviewing related legislations & regulations and domestic & overseas literatures. The devised duties were reviewed by 16 current teachers and 3 education experts to be revised and supplemented to complete the job model. Based on this, development of research tool was finalized, and questionnaires were used as the research tool. The results of this study are as follow. First, the job categories of teachers working at secondary level technical vocational education institutes consisted of 7 categories that are subject instruction, student instruction, class management, curriculum organization & administration, school affairs & administrative duties, PR & field practical training and expertise enhancement. Based on the CFA, they consisted of 46 sub-factors in 10 categories with 3 categories of lesson preparation & planning, lesson administration and academic evaluation for subject instruction, and 2 categories of extracurricular student guidance and school life guidance for student instruction, and class management, curriculum organization & administration, school affairs & administrative duties, PR & field practical training and expertise enhancement. Second, job importance perceived by teachers working at secondary level technical vocational education institutes was found to be high overall with 4.10, while above average in difficulty with 3.45 and average in frequency of performance with 3.12 (1-3 times a month). As for categories with high job importance, they were found to be in the order of academic evaluation (4.32), lesson preparation & planning (4.28), expertise enhancement (4.27), lesson administration (4.26), school life guidance (4.25), class management (4.17) and PR & field practical training (4.12). In regards to categories with high job difficulty, they were found to be in the order of PR & field practical training (4.07), curriculum organization & administration (3.73), expertise enhancement (3.55), school life guidance (3.48), academic evaluation (3.35) and extracurricular student guidance (3.22). As for categories with high frequency of job performance, they were found to be in the order of class management (3.88), lesson administration (3.77), school life guidance (3.52), school affairs & administrative duties (3.40) and lesson preparation & planning (3.17).