Korean secondary students in K region responded to surveys about how satisfied they were with their teachers and their favorite characteristics of teachers that helped determine their achievement and adjustment in classes. We conducted a factor analysis of the students' perceptions of the qualities of their favorite teachers and factor scores across students' grade levels. Our findings indicate that the participants considered five major factors in their evaluation of favorable teachers: communication, life guidance, class management, affective skills, and appearance. Of these, students valued affective aspects, such as communication, life guidance, and affective skills, the most highly. Students' preferences for affective skills intensified as they advanced from middle school grade 1 to high school grade 3. The current study is expected to contribute to developing an understanding of students' perspectives, which has been neglected in previous research.