This study aimed to examine the effects of argument-based chemistry laboratory investigations using the Science Writing Heuristic (SWH) approach on students` use and embedding of multimodal representations in summary writing. Participants of this study were thirty-nine freshman students majoring in science education at a National University in Korea. Argument-based chemistry laboratory investigations using the SWH approach were implemented for twenty-three students enrolled in one cohort, and the traditional chemistry laboratory teaching was implemented for 16 students enrolled in the other cohort. Summary writing samples were collected from students before and after the implementation. Summary writing samples produced by students were examined using an analysis framework for examining the use and embeddedness of multimodal representations. Summary writing was categorized into one of verbal mode, symbolic mode, and visual mode. With regard to the embedding of multi-modal representations, summary writing samples were analyzed in terms of ``constructing understanding,`` ``integrating multiple modes,`` ``providing valid claims and evidence,`` and ``representing multiple modes.`` Data analysis shows that the students of the SWH group were better at utilizing and embedding multimodal representations in summary writing as they provided evidence supporting their claims. This study provides important implications on pre-service science teacher education.