With the rapid development of smart devices, the internet of things, cloud computing, and artificial intelligence technologies in recent years, wearable systems bring opportunities for the application of the elderly’s fall detection. Fall accidents are an important issue in seniors’ care, and the lack of rapid response to these accidents will lead to severe physical and mental injuries to the elderly. To reduce the risk of sequelae caused by fall accidents, wearable systems with integrated inertial sensors and range sensors are applied to detect fall accidents in real-time and notify caregivers for immediate assistance. In addition, falls are related to the balance ability of elderly people. By distinguishing the balance ability of the elderly for long-term activities to detect the balance disorder situation, a fall prevention strategy can be formulated to reduce potential accidents.