The present invention relates to a technology for measuring HF high-vibration-state particle number distribution by using low-resolution near-infrared fluorescence spectrum, wherein the technology is based on the spontaneous radiation fluorescence spectrum technology, and is a new method for measuring the HF molecule high vibration excitation state energy level particle number distribution. According to the present invention, the method is mainly applied in the technical field of chemical laser test diagnosis, and is produced for simplification of the vibration excitation state particle number distribution measurement in the HF chemical laser system; with the method of the present invention, only the intensities of a plurality of P branch spectrum lines of the HF fundamental frequency spontaneous radiation fluorescence spectrum are subjected to simple adding, and characteristics of simpleness, convenience, high precision, non-invasion and the like are provided; and with the method of the present invention, the rapid measurement on various energy levels of the high vibration excitation state particle number distributions in the HF chemical laser can be achieved.