Korean teachers observe and analyze their classes from a reflective point of view. They directly observed videos of their classes and interpret the class. Through this process, the teacher plays the role of a subject who interprets his/her class, and in the process, he/she can look at his/her class as a whole. In this study, 50 selfclass observation reports were collected, and analyzed using the NVivo 12 program. As a result of the analysis, 362 contents of self-reflection by teachers were found, and these were categorized into teacher factors, learner factors, class factors, and environmental factors. Among them, the most reflective content was on class factors. The content was about the problems and difficulties that the teacher encountered in the process of preparing and conducting the class. In order to improve a Korean teacher's class expertise and class quality, it is necessary for the teacher to view and interpret his/her own class from a reflective point of view. Therefore, it is necessary to continuously provide opportunities for class reflection so that teachers can improve their own classes.