The invention discloses a rapid terahertz continuous wave scanning imaging system and method and aims at providing a rapid terahertz continuous wave scanning imaging scheme. With the adoption of the scheme, the scanning imaging speed is increased, the resolution ratio is improved, and the system can stably operate at room temperature for a long time. Therefore, with the adoption of the technical scheme, according to the rapid terahertz continuous wave scanning imaging system and method, the terahertz radiation is subjected to beam splitting, and the signal to noise ratio of an imaging result is increased by introducing reference light; signal light is focused to vertically radiate to a sample, the sample is fixed on a two-dimensional translation stage, the scanning imaging is realized by changing the sample position, the two-dimensional translation stage is stable in moving speed without pause, the intensity values of the signal light and pump light are detected by using detectors of the same model, data of two terahertz detectors at corresponding positions are recorded according to the position of the translation stage, and the terahertz transmission scanning imaging result of the sample is obtained by comparison. The system and the method are mainly applied to the terahertz continuous wave scanning imaging.