The invention discloses a dispersion tensor imaging method. The method is characterized by comprising the following steps of: calculating a probability density function; performing variable density sampling according to the probability density function to acquire data corresponding to a dispersion-free image and multiple dispersion images; and rebuilding the data corresponding to the dispersion-free image and the multiple dispersion images to acquire a rebuilt image. By calculating the probability density function and performing variable density sampling on the data of the dispersion-free image and the multiple dispersion images according to the probability density function in the dispersion tensor imaging method, the data to be sampled are greatly reduced, the acquisition time is greatly reduced, and quick dispersion tensor imaging is realized. Moreover, the invention also provides a dispersion tensor imaging system.