The Internet of things (IoT) is a kind of advanced information technology, it got the attention of abroad and domestic experts and scholars and government departments. This paper introduces the basic characteristics, the key technologies, the network architecture and security problems of the Internet of things. The Internet of things has three aspects of the obvious characteristics of overall perception, reliable transmission and intelligent processing. The key technology includes radio frequency identification (RFID) technology, sensor technology, network communication technology, embedded system technology etc. The network architecture of the Internet of things is divided into sensing layer, transport layer and application layer. Finally, this paper proposed a solution of the Internet of things security problems.