Abstract:In the knowledge economy times, strengthening the sharing of tacit knowledge has became an important factor in promoting postgraduates’ innovative abilities in research. The informal networks have a positive impact on the sharing of tacit knowledge and are also a powerful medium , especially on the personal level. This paper, based on the introduction of the content on postgraduate research tacit knowledge sharing and the relation with informal networks. Then, informal networks are analyzed emphatically the factors which affect the sharing on tacit knowledge. Finally, this paper put forward the effective path of achieving the sharing about postgraduate research tacit knowledge under the informal networks perspective, in order better to promote the cultivation of postgraduate’ innovative abilities in research.