The Internet of things is a current hot topic, and optical fiber sensor technology application in the Internet of things has already caused wide concern. The Internet of things is consisted of four levels. They are user and application interface, data processing technology, data transmission network and sensor network. A large number of varied sensors are needed in the Internet of things. Sensor can perceive all kinds of environmental parameters like temperature, gravity, photo-electricity, sound, displacement and vibrate to provide the original data information. The structure of the sensor, classification, and its applications in the Internet of things like optical fiber gyro, optical fiber hydrophone, optical fiber grating sensor and optical fiber current sensor are introduced. Forefront application in the Internet of things of continuous distributed optical fiber sensing technology based on Brillouine effect is also introduced.