This research is motivated by the fact that students are still found to exhibit undisciplined behavior, are impolite towards teachers, and have low awareness in implementing school regulations at Senior High School 12, Jambi City. This condition shows the importance of the role of Islamic Religious Education teachers in fostering and shaping student behavior to be in accordance with religious values and applicable social norms. This research is a qualitative research with a descriptive approach. The research was conducted at Senior High School 12, Jambi City. The research subjects consisted of Islamic Religious Education teachers and students. The types of data used are primary data and secondary data, with data sources in the form of humans, learning activities, and supporting documentation. Data collection techniques are carried out through observation, interviews, and documentation. Data analysis techniques include data reduction, data presentation, and drawing conclusions. Data validity is obtained through extended participation, persistent observation, and triangulation. The results of the study indicate that: (1) forms of student behavior that need to be fostered include lack of discipline, low politeness, lack of responsibility, and behavior that does not reflect Islamic values; (2) factors causing student behavior are influenced by the family environment, peerinteraction, use of social media, and lack of supervision and habituation of positive behavior; and (3) efforts by Islamic Religious Education teachers in fostering student behavior are carried out through providing advice and motivation, role models, habituation of religious activities, individual approaches, and collaboration with parents and schools in monitoring the development of student behavior.