The invention relates to a method for extracting TiO2 from white clay. The method comprises steps as follows: (1), an alkaline solution is added to the white clay, Al2O3 and SiO2 are leached, and filter residues a are collected; (2), the filter residues a are leached in a leaching liquid, CaO, MgO, Fe2O3, Na2O, K2O and the like are removed, and secondary filter residues b are collected; (3), sulfuric acid is added to the filter residues b, TiO2 is extracted, and a filtrate c is obtained; (4), the filtrate c is heated and concentrated, pH of the filtrate is regulated to 2.5-4.0 with the alkaline solution, then the filtrate is mixed with hot water, the mixed solution is heated to be boiled, TiOSO4 is hydrolyzed, solids obtained through hydrolysis are calcined, and TiO2 with the purity higher than 94% is obtained finally. According to the method for extracting TiO2 from the white clay, CO2 in the white clay can be effectively extracted, the process of the method is simple, the product purity is higher, the white clay is comprehensively utilized, the economic benefit is produced, and the method plays an important role in the aspects of increase of economic output and reduction of environmental pollution.