The invention relates to peptization method of pseudo-boehmite. The peptization method comprises the following steps: (1) pulping pseudo-boehmite and water, and uniformly dispersing; (2) adding soluble salt with anions of Cl<-> or NO3<-> or CH3COO<-> or COOH<->, stirring, and standing; and (3) finally uniformly stirring pulp in the step (2), and adding acid until the pulp becomes a transparent colloid. By virtue of the peptization method, the pseudo-boehmite can be completely peptized, and the peptization degree is equal to the peptization of hydrochloric acid and nitric acid, so that a hydrochloric acid peptization agent and a nitric acid peptization agent are replaced with the pseudo-boehmite, the environmental pollution caused by the volatilization of hydrochloric acid and nitric acid is reduced, and the selection flexibility on the peptization agents of a production enterprise is increased, the peptization speed is controllable, and the fluidity of the pulp is good; and the heating is not required during the peptization, so that the energy consumption of the production enterprise is reduced.