Cooperative learning (CL) has strong potential to be implemented in Indonesian schools. The notion of learning together, teaching, and sharing with one another is attractive and promising, not only because of the potential for higher achievement demonstrated in prior research from the West (Cohen, 1994; Johnson & Johnson, 2009), but also because of potential for cultural aptness, in the Indonesian context which is a society culturally oriented towards collectivism rather than individualism (Hofstede, Hofstede, & Minkov, 2010). In addition, Indonesian cultural values – gotong royong (mutual assistance) and musyawarah (consensus decision-making) (Darmaputera, 1988) – are aligned with CL principles (Prastyo, 2014). Despite the well-documented advantages of CL, teachers find CL difficult to apply in the classroom (Johnson & Johnson, 2008). The findings of previous research in Indonesian education revealed that teaching in most classrooms remained traditional and dominated by rote learning, although recently curricula have been designed to make learning more engaging to students (Bjork, 2013; Heyward, 2014). The Indonesian school strong tradition of teacher-directed instruction, insufficient teaching facilities, and inadequate professional development for teachers have contributed to teachers’ reluctance towards using social constructivist approaches (Bjork, 2005) such as CL. Greater attention is needed to investigate teachers’ beliefs about CL in the context of Indonesia, where the cultural values support CL principles but its instructional traditions and institutional factors impede the application of CL. This study is situated in interpretative-qualitative methodology using a multiple case study approach (Stake, 2005). Two phases comprising teacher interviews, classroom observations, post-observation interviews, and field notes were conducted to investigate teachers’ espoused and enacted beliefs about CL. Teaching documents were examined. The findings were analysed using Fives and Gill’s (2015) ecological model of teachers’ beliefs drawing from Bronfenbrenner’s (1989) work of socio-ecological model. Initial findings of the data analysis of Phase 1 will be presented at the AARE conference. The complexity of Indonesian teachers’ beliefs will be presented through the lens of socio-ecological model.