With the increasing globalization, R&D outsourcing becomes an effective approach for utilizing external resources and improving companies’ innovative capacity. Therefore, knowledge leakage has attracted wide attentions both from the industry and the academia. This study adopts Honeywell China Branch as a case study of R&D outsourcing, from which both internal and external risk mitigation mechanisms as well as a theoretical model are inductively developed. This study contributes to and provide valuable knowledge base for the management of the R&D project and the mitigation of knowledge leaking risks.