Abstract: Using the industrial titanium liquid as the raw material,the hydrolysis was carried out by external seeding.The effects of titanium liquid index including TiO₂ concentration,F value,Fe/TiO₂ ratio and Ti³⁺ concentration on the hydrolysis rate were investigated.Then,the relationship between the hydrolysis rate and the index of titanium liquid was deduced by hydrolysis equilibrium theory.The results show that with the increase of TiO₂ concentration,the hydrolysis rate decreases.With the increase of F value,the hydrolysis rate decreases sharply.With the increase of Fe/TiO₂,the hydrolysis rate also decreases.With the increase of Ti³⁺ concentration,the hydrolysis rate is on a downward trend.The theoretical derivation results show that at the same dilution ratio,the hydrolysis rate at the equilibrium is linear with the product of the total titanium concentration and the square F value,and the intercept is related to the concentration of Ti³⁺.