The teacher plays an important role in implementing the curriculum. Moreover, the teacher who has adequate knowledge and skill in implementing the curriculum will be able to achieve the expected student outcomes. School as the educational institution has the responsibility to empower and equip the teacher. Therefore, sustaining curriculum involves the school to empower the teacher to share their knowledge, which by the servant leadership and organizational citizenship behavior, there will be a knowledge that is developed. This study is aimed to determine the relationship of servant leadership, organizational citizenship behavior, and knowledge sharing to curriculum sustainability. The subject of this study was 98 teachers of Cahaya Bangsa Classical, a Christian school in Bandung. This study uses a quantitative approach with a path analysis method with the saturated sample to determine the effect of each variable. The result shows that servant leadership and organization citizenship behavior has a positive relationship to knowledge sharing and curriculum sustainability through the mediation of knowledge sharing. Organization citizenship behavior has a negative relationship to curriculum sustainability. The organization's ability to maintain and sustain the curriculum with qualified teachers makes graduation that aligns with the school vision and mission.