With repatriates in Multinational Corporation as the subjects this present study empirically investigated the impact of repatriation support on ambidexterity innovation, and explored the mediating role of knowledge transfer as well as the moderating role of self-efficacy in the relationships of repatriation support with exploitive innovation and exploratory innovation. A moderated mediation model was further tested. By using hierarchical regression analysis, it was revealed that repatriation support has significant positive effect on knowledge transfer, and knowledge transfer has significant positive effect on exploitive innovation and exploratory innovation, respectively; knowledge transfer plays a mediation role in the relationship of repatriation support with exploitive innovation and exploratory innovation, and the mediation role has difference, knowledge transfer partial mediates the relationship between repatriation support with exploitive innovation, while fully mediates the relationship between repatriation support with exploratory innovation. The findings also indicated self-efficacy plays a moderation role in repatriation support and knowledge transfer. By employing bootstrapping, the results demonstrated that self-efficacy moderates the effects of repatriation support on exploitive innovation and exploratory innovation via knowledge transfer such that the effects are stronger when self-efficacy is higher.