The ability of the brain to accurately position limbs diminishes with age. Virtual-reality head-mounted displays (VR-HMDs) that obscure real-world limbs may be ideal for training this ability. However, the use of VR-HMDs poses significant challenges to the older population. This study developed a VR game accessible to older adults without prior VR-HMD experience and monitored brain function changes after 3 weeks of regular use. All participants succeeded in operating the device independently after 30 min of instruction and played a simple target-reaching game at home during this period. Functional magnetic resonance imaging at rest before and after the game showed a significant correlation between game performance improvement and the connectivity of brain regions related to motor function. The proposed VR-HMD game could be acceptable to older beginners and may enhance their motor function for accurate limb movements.