In the present paper, the basic principles, the device and the analytical method of the hydrodynamic chromatography (HDC) were summarized, which is most widely used in hydrokinetic chromatography.  The application of the hydrodynamic chromatography in the determination of the particle size and size distribution of the particulate drug delivery system was also reviewed.  The method can determine the particle size of nano- and micron-scale particulate drug delivery systems rapidly.  And this method also has the advantages of economic, convenient and no damage to the samples.  In summary, there will be a good prospect for the application of HDC in the determination of particle size distribution features of particulate drug delivery systems.