In times of globalization and rapidly developing R&D systems, the importance of international collaborative research activities increases, leading to a growing number of heterogeneous collaborations. Especially considering the cultural diversity of such collaborations, intensive cross-cultural knowledge sharing becomes a prerequisite for collaborative success. This paper investigates personal and cultural incentives and barriers influencing the intention to share knowledge of Chinese and German collaborators in an academic setting, employing a linear regression analysis and Chow tests. We can demonstrate that the factors sense of self-worth, loss of knowledge power, guanxi and face saving have an influence on an individual’s intention to share knowledge. Further we find significant differences in our Chinese and German subgroups that can be related to cultural impacts. The obtained results provide practical and theoretical implications for the improvement of cross-cultural knowledge sharing in collaborative R&D project.