Alzheimer’s disease (AD) is the most common form of dementia, which is a global growing issue in the foreseeable future. Few studies focused on the ability to ride a motorcycle in patients with AD. We built a dynamic motorcycle simulator with a scenario of possible traffic accident. Functional near-infrared spectroscopy was done to monitor the activation of bilateral prefrontal cortex. 55 participants were recruited (Healthy control (HC)/Mild cognitive impairment (MCI)/AD = 24/20/11). A cognitive battery was done. During simulated riding, the time between participants seeing the incident and squeezing the brake was recorded as the reaction time of incident (RTI). The result show that the brain contra-lateral to the event had higher activation in patients with AD and MCI. AD patients had a significant longer RTI than HC (p = 0.046), RTI was not correlated with items in cognitive battery. In this study, we showed that AD patients had worse ability to ride a motorcycle. We also proved the viability of the design. Future studies with more scenarios and participants are warranted.