According to the difference of acid dissolved titanium slag and ilmenite, the laboratory experiments of preparing titanium white from acid dissolved titanium slag were carried out. The acid dissolved titanium slag came from respectively smelting Panzhihua ilmenite and Yunnan ilmenite. The process parameters of digestion and hydrolysis were defined by the laboratory experiments, and the results showed the process of producing titanium dioxide by acid dissolved titanium slag was feasible. The digestion rate of water quenching slag was higher than that of without water quenching slag under same conditions. The optimal hydrolysis process parameters are:the TiO2 concentration in hydrolysis process should be more than 200 g/L, the add quantity of nucleator should be 1.3%~1.5%, and the Ti3+ concentration in hydrolysis solution should be 1~3 g/L.