Abstract: This paper focuses on the collaborative mechanism for Collaborative Concept Mapping.Aiming to supporting an effective collaborative concept mapping system, this paper proposed a meaning negotiating mechanism, which deals with the consistency maintenance issue by supporting students' negotiating on cognitive conflicts.Also by using the mechanism, the inconsistent issues resulted by saving cognitive conflicts in collaborative knowledge construction process is accomplished as well.The test result shows that the mechanism is feasible and effective in the collaborative concept mapping system.