The qualitative case studies in socioscientific issues (SSI) focus on teachers' perceptions and opinions on teaching SSI, rather than individual teachers' involvement in teaching SSI. Thus, there is a need for in-depth case studies that focus on teachers' practices of teaching SSI and how these practices are influenced by teachers' deeper beliefs and motivations. This study investigated science teachers' design and implementation of SSI-based instruction. Using a multiple case study design, the participants were three science teachers. The data collected through semi-structured interviews, observational field notes, and reflective journals in this study. The data analysis procedure occurred in three stages: open coding, identification of patterns and categories, and building themes. The findings revealed that one participant embraced the inclusion of social aspects such as ethics and values in SSI instruction, whereas the other two participants intentionally excluded the social aspects and only focused on scientific data and findings in order to present the issue in a less biased and controversial way. In addition, teachers' epistemological and pedagogical beliefs about science and socioscientific issues, as well as the social and cultural structure of their school and community, strongly influenced their SSI-focused instructional practices.