The emerging pervasive computing is regarded as a promising solution to the systems of personal healthcare and emergency aid, which can monitor personal health status in a real-time manner and automatically issue the alert for medical aids in case of emergency.Our system does not require specific caregiver aid. It just employs the tiny wearable sensors to continuously collect user's vital signals and Zigbee device to transmit the sensory data to a computer, which can perform on-site vital data storage and process. After local data process, the mobile phone can use its GSM module to periodically report users health status to the healthcare centre and issue alert for medical aids once detecting emergency. This system can satisfy the requirements of real personal healthcare and emergency aid system.