ABSTRACT Collaborative argumentation supported by argumentation mapping is important for developing college students’ argumentation ability. However, in conventional argumentation mapping-supported collaborative argumentation (AM-CA) activities, learners tend to quickly reach consensus without sufficient discussion and negotiation, or fail to spontaneously assess and integrate the group’s ideas, thus failing to develop more comprehensive and in-depth arguments. Therefore, this study proposed a six thinking hats strategy-based dialogic peer feedback approach to support AM-CA activities, which was expected to support students’ iterative negotiation and deeper interactions through dialogic peer feedback, thus enhancing the quality of argumentation. To show the effectiveness of the proposed approach, this study used a quasi-experimental method to test the proposed strategy in a freshman seminar class at a university. The control group (22 students) used the conventional AM-CA (C-AM-CA) approach, while the experimental group (22 students) used the six thinking hats strategy-based AM-CA (STH-AM-CA) approach. The findings showed that STH-AM-CA improved the quality of argumentation mapping compared to C-AM-CA, but it also significantly increased the learners’ cognitive load. In addition, a thematic inductive qualitative analysis of the interview data demonstrated the strengths and weaknesses of each strategy.