With the rapid arrival of the mobile information era, it has promoted the rapid progress and continuous development of modern Internet and other information electronic technologies. Based on the concepts of the Internet of Things and healthcare, a remote health monitoring system was studied based on Narrow Band Internet of Things(NB-IoT).The system consists of an smart bracelet, an Android client of the user's mobile phone, and a medical monitoring center's PC terminal. The smart bracelet can record the user's heart rate and body temperature and other daily physical conditions, as well as information such as exercise status and accidental falls. And an Android mobile app that could register and log in to the smart bracelet's vital signs in real time was developed, a control experiment on the accuracy of the data collected by the smart bracelet was conducted, and the collected information is transmitted to one net cloud service platform through NB-IoT. One net cloud service platform, transmitting data with the mobile phones of users and their families and the PC terminal of the medical monitoring centre through the network, could establish an alarm system based on Android. Finally, the feasibility of the portable monitoring device was verified by working performance test and data transmission reliability test. Improving the quality of daily life of the elderly and releasing the pressure of society and offspring, this system can solve the health problems of the elderly.