Purpose: The study explores African partners' experiences regarding Chinese expatriates' knowledge control practices in 29 Sino-African joint ventures in 12 countries. It provides insights into power dynamics and knowledge transfer (KT) from African partners' perspective. Design/methodology/approach: The qualitative paper mobilized semi-structured interviews with Africans who worked with Chinese expatriates across Africa. The study focused on understanding the experiences of African partners when collaborating with their Chinese expatriate colleagues on assignments in joint ventures (JVs) in Africa. Findings: Chinese expatriates employed five tactics, as described by African partners, to control knowledge based on power, behaviors and knowledge type. Particularly, through the lens of unofficial power, this study explains knowledge hiding tactics between knowledge-holding Chinese expatriates and host country knowledge-seeking locals. A new dimension of authority-based knowledge hiding is discovered. Originality/value: The paper brings new insights into the analysis of power (official and unofficial) boundaries regarding knowledge control mechanisms in joint venture collaborations between employees from China and Africa. Unofficial power appeared as a major leverage for expatriates in monopolizing their strategic knowledge. The study recommends mobilizing African diaspora and repatriates from China to improve KT for Africa.