This research focuses on investigating the contribution of school culture to students' academic achievement. To this end, a mixed research approach was used. 82 teachers, 258 students, 5 school principals, and 3 school cluster supervisors were the data sources of this study. To see the contribution of school culture to students' academic achievement, questionnaire for students and teachers, interview with school principals and cluster supervisors were used. Percentages and one sample ttest were used to analyze the data. The quantitative data confirmed that the contribution of school culture to students' academic achievement was found statistically significant but slightly above the expected mean. Qualitative data from the respondents showed strong communication among stakeholders during the implementation process. The support system from teachers and other responsible bodies were seen as effective. A guideline that specifies teachers' responsibility and the program implementation process, such as continuous follow-up and supervision were reported relevant and triggering teachers to live up to the minimum teachers' professional commitment standard. Generally, both the qualitative and quantitative data analysis results revealed a moderate level contribution of school culture to students' academic achievement. As this result was not much encouraging, appropriate strategies of enhancing the contribution of school culture to students' academic achievement were pointed out in the paper.