Abstract: Based on NVivo, a video analysis software, 12 award-winning videos of heteromorphic lessons on the same topic in the "National Middle School Physics Young Teacher Teaching Competition" were investigated with the help of improved Flanders interactive analysis system PFIAS, the S-T method and lag sequential analysis (LSA). The characteristics of the teaching behavior structure, the behavior interaction and the behavior tendency of young teachers were comprehensively analyzed through the behavior ratios, teaching mode and significant behavior transformation in the high-quality class in order to provide models and references for future young teachers. The results show that in the high-quality class the teachers stimulate students' learning motivation with praises, acceptance and empathy and indirectly guide students to answer questions and explore actively, which results in a harmonious classroom atmosphere. The ratio of teachers' behavior to students' is appropriate and the behavior conversion rate is moderate in most classes, which conforms to the mixed teaching model. Multiple interactions with behavior stability and strengthened interaction between operational behavior sequence and IRF are observed as the main features of behavioral interaction, which shows that the interaction is reasonable and orderly. From the perspective of development trend, students' status as the subject of cognition is gradually strengthened. It is noted that more open questions with less presetting traces are needed in high-quality class.