In order to provide a solution for transient high-temperature measurement under special circumstances, an optical fiber high-temperature sensor and dynamic calibration system based on the mechanism of blackbody radiance are designed. According to the basic principle of radiance temperature measurement and combining the sensor technology of optical fiber, “touchable-untouchable” measuring method and “fiber grating narrowband filters” technology are used to improve the measuring accuracy and decrease the influence of light background. Because the transient temperature changing very quickly with time and dynamic response error is great, a new principle is proposed. A high frequency modulated high power CO2 laser is used as the driving source to heat up the sensor calibrated. Using the temperature signal obtained, high-temperature dynamic calibration can be carried. The testing results show that the temperature measurement range is from 800～2000 ℃, and the system has many advantages such as high accuracy, fast response, anti-electromagnetic disturbance as well as high reliability. It solved the limitation of thermocouple, such as slow response and short life, and provided a new measuring method to transient high-temperature measurement in metallurgy, petroleum, industry and weapon development fields.