The invention provides an ultra-fast transmission electron microscope system which comprises an ultra-fast laser system, an electronic gun, an illuminating system, an imaging system, a sample chamber, a detector and a vacuum device, the ultra-fast transmission electron microscope system can particularly test ultra-fast structure change processes of samples under different laser parameters and environmental temperature, the different laser parameters include different excitation wavelengths, pulse width, laser power, repetitive frequency, sample temperature and the like, acquired signals comprise diffraction, microscopic images, energy loss spectroscopy and the like, and the ultra-fast structure change processes are analyzed by analyzing position and strength of diffraction peaks, image contrast change and the like.