This article examines the role of humour in the mainly under-researched context of HIV/AIDS consultations in Malawi. Using audio-recordings of seven antenatal HIV/AIDS counselling sessions conducted in Chichewa (Malawi's national language) in a rural hospital, the paper elucidates how the counsellors skilfully employ the multiple and often inconsistent functions of humour (Schnurr and Plester, 2017) to engage the pregnant women in the negotiation of knowledge and to assure they have grasped vital information about precluding HIV/AIDS from spreading to their unborn child. The counsellors in these sessions employ humour to strengthen solidarity, generate a friendly atmosphere, and ease the debate of sensitive or taboo topics, as well as to criticise and reprimand the pregnant women for their lack of knowledge of HIV/AIDS, their lifestyle, and their lack of engagement with the counselling. Due to its ability to accomplish these very equivocal functions – sometimes concurrently– humour is an outstanding means to aid the counsellors in attaining their aims.