Parents play essential roles in children’s play and learning with various media, often leading to positive and productive engagement outcomes for both parties. As such, an increasing number of HCI research has focused on understanding parent-child joint media engagement (JME) and designing new technologies to foster productive joint media experiences for children and parents. However, we currently lack a systematic view of this emerging field, which hinders the research and design of new joint media experiences and technologies for families. In this work, we conduct a scoping review of parent-child JME research within HCI (N = 89) and analyze the included papers from three lenses: publication features, methodological features, and JME features. Based on these findings, we identify gaps and opportunities in parent-child JME research and further expand the theoretical framing of JME by developing a framework that captures different JME dimensions.