This study aims to determine the influence of the school environment on students’ multicultural attitudes, the influence of religious activities on students’ multicultural attitudes, and the simultaneous influence of these two variables. The study was motivated by the diversity of students’ religions, cultures, ethnicities, personalities, and social backgrounds, which necessitates fair and inclusive educational management. This study employs a quantitative approach with an associative research design. The study sample consisted of 115 students from SMP Plus Melati Samarinda and SMP PGRI 7 Samarinda. Data were collected through questionnaires and documentation, then analyzed using multiple linear regression with the aid of SPSS. The results showed that the school environment had a positive and significant effect on students’ multicultural attitudes, with a regression coefficient of 0.327, a calculated t-value of 8.746, and a significance level of 0.000. Religious activities also had a positive and significant effect, with a regression coefficient of 0.384, a calculated t-value of 7.448, and a significance level of 0.000. Simultaneously, both variables had a significant effect on students’ multicultural attitudes, with a calculated F-value of 104.332 and a significance level of 0.000. The coefficient of determination of 0.651 indicates that the research model explains 65.1% of the variation in students’ multicultural attitudes. This study underscores the importance of an inclusive school environment and religious activities that foster tolerance, respect for differences, and harmony.