According to statistics report, there are estimated 24.3 million dementia patients, and will be two-fold increment in every twenty years. For the increasing loss way events in dementia patients and elderly people and even results in mortality in recent years, In order to reduce these disasters, we explore the ??Tracking and warning systems for the preventing loss in elder people with dementia.?? This product contains the APP for 3G remote communication capabilities on the Android mobile phone chips, and could stick on clothes. The family member can remote control the screen at home and then produce LED marquees to notice the information to the passers for the aid or to contact with his family members immediately. In addition, the family can turn on GPS positioning system that allows them or related ambulance unit immediately find a missing elder person.