Promotion of students' scientific literacy has long been and continues to be a central goal for reform efforts in science education. Although there is a great number of research conducted to evaluate student's scientific literacy, less is known about how we can improve students' scientific literacy through variety of scientific practices. In this study we aimed to refer to this shortcoming in the literature by examining the effect of argument driven inquiry (ADI) instructional model to promote 8th grade students' scientific literacy. A mixed method quasi experimental design was used in this study. Sixty-seven eighth grade students from the same public school attended the study. Two intact classes were randomly assigned either in structured inquiry (SI) or ADI groups. The data sources included a Scientific Literacy Assessment (SLA) and semi-structured interviews. The results indicated that students experiencing ADI instruction scored higher on the SLA-D test and personal epistemology dimension of SLA-MB test than students experiencing SI instruction. The results propose that engaging students in meaningful scientific practices may support their scientific literacy.