Character building is a crucial process that involves educators, parents, and society. In the era of globalization, the challenge of moral crisis among adolescents—particularly among Vocational High School (SMK) students who are predominantly in adolescence—is increasing. Islamic Religious Education (PAI) has a dominant role as a moral, ethical, and spiritual foundation to counter negative behavior and produce a generation with the character of insan kamil. SMK Muhammadiyah 3 Klaten Utara has a vision to produce graduates who are devout, have noble character, and are competent. However, in reality, there are still some students who violate school rules and norms, so optimal strategies from PAI teachers are needed in internalizing these values. This study aims to deeply analyze the strategies and efforts carried out by PAI teachers in instilling the values of Islamic Religious Education (PAI) in order to shape the character and personality of grade X students at SMK Muhammadiyah 3 Klaten Utara. This research is field research with a descriptive qualitative approach. Data were collected through preliminary observation and documentation. The results of the study show that student character is closely related to PAI values which function as the development of faith, life guidance, mental adjustment, behavioral improvement, and prevention of negative impacts. The instillation of PAI values at SMK Muhammadiyah 3 Klaten Utara is implemented through a holistic approach that focuses on teacher role modeling, the creation of a religious environment, and the consistent habituation of positive behavior both inside and outside the classroom (such as religious values, honesty, discipline, responsibility, and tolerance).