While most educational models point toward cognitive and metacognitive skills to promote reading comprehension, recent studies indicate that motivation also plays a key role. Consequently, studying social factors that may support reading motivation represents an interesting research avenue. We therefore performed a systematic review of the literature to highlight the types of reading support provided by teachers, parent, or peers that predict changes in reading motivation among students in grades 4 to 6. Restricting our sample to peer-reviewed articles published in the last twenty years, we identified 7208 research papers from electronic databases. From these, we selected papers focused on 4th to 6th graders with normative development, using reading supports (from either teachers, parents, or peers) as independent variable(s) and reading motivation as the dependent variable, and having at least two waves of data. At the end of the selection process, 16 studies were eligible for data extraction. Our synthesis suggests that the current state of research in the field of reading motivation does not allow the identification of reading interventions that are undoubtedly effective in promoting reading motivation. However, it appears that supporting students' psychological needs is generally an effective way of producing positive changes in their reading motivation.