On the basis of concept, characteristics and related work of collaborative learning, this paper proposes a practical and efficient way based on multi-agent technology. At first, the paper introduces a collaborative learning framework which supporting group learning and illustrated the whole learning process. Secondly, the paper presents some key issues to implementation of the virtual learning environment, such as intelligent grouping, intelligent question & answer system, knowledge management, evaluation of group-learning effectiveness. Learning practice verifies the validity of the system.