This study describes the teaching style behaviors that differentiate between learner-centered and teacher-centered approaches to teaching. The Teaching Style Assessment Scale, which measures teaching style, was completed by 1,261 nursing faculty in Japan. Discriminant analysis and cluster analysis revealed that the distinctive characteristic distinguishing the learner-centered approach from the teacher-centered approach is Personalizing Instruction. Personalizing Instruction recognizes and utilizes the uniqueness of each student's strengths. Personalizing Instruction can facilitate students' interpersonal understanding and self-awareness. By implementing Personalizing Instruction, teachers can facilitate the metacognitive process in their students, which is healthy for the individual and productive for meaningful learning. Learner-centeredness embraces Personalizing Instruction, while teacher-centeredness rejects it. Teachers practice learner-centered and teacher-centered styles nearly equally. Personalizing Instruction is the most critical teaching style element and the indispensable definitive factor separating these styles.