The invention discloses a ballastless track slab temperature high speed dynamic measuring system. The ballastless track slab temperature high speed dynamic measuring system is used for measuring the temperature of a ballastless track slab; the ballastless track slab temperature high speed dynamic measuring system is mounted at the bottom of a train; and the ballastless track slab temperature highspeed dynamic measuring system comprises an optical information collection module, a photoelectric temperature measuring module and a temperature control box, wherein the optical information collection module is used for collecting spectral information of a sampling point of the ballastless track slab and transmitting the spectral information to the photoelectric temperature measuring module, thephotoelectric temperature measuring module is used for converting the spectral information into an electric signal and calculating the temperature of the sampling point according to the electric signal, and the temperature control box is used for adjusting the temperature of a working environment of the photoelectric temperature measuring module. According to the ballastless track slab temperaturehigh speed dynamic measuring system, with the train as a carrier, the temperature of the ballastless track slab of a railway line can be measured at a high speed in real time, and spatial sampling iscarried out at an equal interval of 250 mm to measure the temperature of the ballastless track slab under a double-direction (a forward direction and a reverse direction) running condition with trainspeed of 400 km/h in a high temperature or cold environment (a temperature range from a low temperature of -40 degrees to high temperature of 60 degrees).