This study explored the construction of power relations in the cognitive assessment of older adults within the Chinese clinical context. Data is derived from audio and video recordings that nine older adults produced in the cognitive assessment of the Chinese version of the Montreal Cognitive Assessment-Basic (MoCA-B), which were then annotated and analyzed from a multimodal pragmatic perspective. The study reveals that examiners and older adults employed various speech acts to achieve distinct communicative goals, with power relations between them being reflected through these speech acts. Examiners tend to claim high power, utilizing discourse strategies such as request, interruption, evaluation, rhetorical questions, and directive speech acts. In contrast, older adults assert high power through directive speech acts, rhetorical questions, and interruptions. Both parties also exhibit low power by using confirming questions and explanations. Additionally, gestures, smiles, prosody features, and other non-verbal communicative resources are synergistically employed to exercise power. The interactive mechanism of constructing power relations reveals that age affects older adults’ power relations construction even in a professional setting of the Chinese context. The negotiation between the advanced age of older adults and the expertise of examiners jointly shapes power relations in their interactions.