This paper reports on a study that investigated group learning processes in computer-supported collaborative concept mapping. Thirty 5th grade Taiwanese students were selected to attend a computer-mediated collaborative concept mapping activity. Dialog messages and map products tracked and recorded by the mapping system were analyzed. The exchanges in the dialog data were divided into four groups: opening a discussion; introducing a concept; establishing a link; and reconsidering the map. According to the analysis of the students' discourse record and group concept maps, it was found that the students took different approaches to develop their group concept maps. Four patterns of the computer-mediated collaborative concept mapping processes were identified: concept introduction first; limited concept introduction; less link establishment; and proposition construction oriented. In addition, different collaborative mapping approaches generated different concept maps. The findings suggest that students in a computer-mediated collaborative concept mapping activity should be guided or instructed to undertake some particular approach to generate satisfactory maps. (Contains 13 references.) (Author/MES)