This study introduces the development of test tools and scoring methods of Korean art essay assessment at high school. This research investigates how to ensure the validity and reliability in the assessment and teachers’ interviews about its necessity and improvement. 140 patients at Bucheon Girls’ High School conducted Reading art second semester final exam on Nov. 15, 2011. and 4 Reading art teachers carried out the development of test tools and scoring. This paper analyzed validity, item discrimination, reliability of Korean language essay assessment. Consequently, the assessment proved to have content validity through experts’ reviews and item discrimination through the analysis of correct and incorrect answer table. It also proved to have construct validity through correlation analysis(.561) between multiple-choice test score and open-ended test score. and it had reliability through raters(teachers) performing consultation process about scoring. Finally, this research conducted the interviews during the teacher concil to understand the teachers’ opinions about Korean language essay assessment. Teachers agreed to the necessity of the assessment, but they emphasized that the development of test tools and scoring method should be theorized systematically and the study of how to reduce assessment tasks should be conducted consistently.