Abstract: Titanium gypsum is a by-product in producing titanium dioxide （TiO₂） by sulfuric acid method. 4~5 tons of titanium gypsum is produced for the production of every one ton of titanium dioxide. The environment pollution of the titanium gypsum can be efficiently resolved by adding the pretreated titanium gypsum to the sintered brick with gangue as main raw material. The influences of calcination temperature,addition amount of clay and titanium gypsum,and heat preservation time on the strength of the sintered brick were investigated by conditional and orthogonal tests. The results of conditional tests show that the strength of sintered brick increases with increase of calcination temperature,heat preservation time and the addition amount of clay,but it decreases with increase of addition amount of titanium gypsum. The results of orthogonal tests show that under a relatively stable addition amount of clay,the influence order of other factors on the strength of sintered brick is addition amount of titanium gypsum ＞heat preservation time ＞ calcination temperature. The optimum parameters are as follows: 14% of titanium gypsum addition,8 h of heat preservation and 1 000 ℃ of calcination.