ObjectiveTo explore the characteristics of balance and cortical activation in older adults when performing cognition-balance dual tasks. MethodsFrom January to April, 2023, 20 healthy older adults were non-targeted recruited. They completed six tasks of close eyes & fixed platform (CF), close eyes & fixed platform & cognitive task (CFc), open eyes & sway-referenced platform (OS), open eyes & sway-referenced platform & cognitive task (OSc), close eyes & sway-referenced platform (CS), and close eyes & sway-referenced platform & cognitive task (CSc) on the Balance SD, wearing functional near-infrared spectroscopy caps. The overal stability index (OSI) was measured with Balance SD. The premotor cortex (PMC), sensorimotor cortex (SMC) and prefrontal cortex (PFC) were as regions of interest (ROIs), and the β values were calculated. ResultsThe OSI was more as CFc than as CF (Z = -2.014, P < 0.05), and was less as CSc than as CS (Z = -2.063, P < 0.05). The β values of bilateral ROIs were all more as CFc than as CF (|Z| > 2.464, |t| > 3.733, P < 0.05), and as OSc than as OS (|t| > 2.308, P < 0.05); the β value of the right SMC was more as CSc than as CS (t = -2.912, P < 0.05). The number of correct counts was less as CSc than as CFc and OSc (|Z| > 3.643, P < 0.001). ConclusionBalance has been impaired under dual tasks for older adults, while activation of cerebral cortex increases. However, for more difficult balance task, older adults would preferentially maintain postural balance under dual tasks, while cognitive performance decreases, which may be the results from no more activation of cerebral cortex under dual tasks.