Background: Evidence regarding the impacts of school-engaged social and behavior change communication (SBCC) interventions on malaria preventive behaviors in rural primary schools is limited. This study examined the effect of the school-based SBCC approach on the utilization of the insecticide-treated nets among primary school students in malaria-endemic settings of Ethiopia.Methods: Engaging primary schools and community; various participatory, educational, and communication interventions were implemented from 2017 to 2019 in 75 rural primary schools in Jimma to promote malaria preventive practices in target the villages. A post-intervention quasi-experimental design was conducted with randomly selected 798 students (i.e. 399 intervention and 399 control groups). Data were collected by trained interviewers using structured questionnaires. The SPSS version 26 software was used to analyze the data. Propensity score matching analysis was performed to control for possible confounding biases. The average effects of the intervention were estimated using multivariate general linear modeling and chi-square tests based on the nature of the outcome data. P-value < 5% was considered for statistical significance. Results: The result showed a significant difference of 39% in the proportion of ITN utilization between the intervention and control groups; (95% CI: 38.23% to 39.77%). The intervention also led to a significant mean differences (MD) of self-efficacy (MD=15.34; 95% CI: 13.73 to 16.95), knowledge (MD=5.83; 95% CI: 5.12 to 6.55), attitude (MD=6.01; 95% CI: 5.26 to 6.77), perceived malaria risk (MD=2.14; 95% CI: 1.53 to 2.76), and perceived family supports (MD=6.39; 95% CI: 5.57 to 7.22). Multiple logistic regression modeling results showed that knowledge (β=0.194, 95% CI: 1.09 to 1.35) and perceived family supports (β=0.165, 95% CI: 1.11 to 1.25) and self-efficacy (β=0.10, 95% CI: 1.22 to 2.32) significantly predicted the ITN utilization among the school children. Conclusion: The finding of this study suggested that the school-based SBCC approach combined with peer education activities advanced the malaria-related knowledge, attitude, self-efficacy, risk perceptions, and family supports and ultimately improved the sustained use of ITNs among school-going children. Further research should be conducted to understand the mechanism of these effects given the influences of social, health services, and school systems are considered.