The invention provides a preparation method of a jelly glue dispersion in-depth fluid flowing diverting agent, comprising the specific steps as follows: during a process when the jelly glue is formed by mixing part of hydrolyzed polyacrylamide and chromium acetate, a peristaltic pump applies a certain shearing force to a gelation system so as to lead the gelation system to form the jelly glue dispersion rather than integrated jelly glue. The jelly glue dispersion prepared by the method consists of jelly glue particles and water; and the particle diameter of the jelly glue dispersion can be controlled by adjusting the shearing speed. The jelly glue dispersion can be injected into the in-depth reservoirs; the adsorption and detention of the jelly glue dispersion particles in the hole can reduce the permeability of the high-permeability area, leads the subsequently injected liquid to be turned to the low-permeability area, and has the function of in-depth profile modification. The in-depth fluid flowing diverting agent has the advantages of low viscosity, good fluidity, good stability, long validity period, and the like, is insensitive to shearing and physical and chemical conditionsof the reservoir, has controllable dimension, can design the diameter of the jelly glue dispersion with the aim of different stratums, and prevents blocking the stratum percolation surfaces.