To get CaTiO3catalyst with high photocatalytic properties,the effect of calcination conditions,on the photocatalytic activity of CaTiO3 was investigated.The calcination conditions included heating rate of calcination precursors,calcination temperature,calcination time and cooling rate of calcination products,The catalyst was synthesized by solid-state reaction method with Ca(NO3)2and TiO(OH)2as raw materials and NaOH as mineralizer.The physical properties of the catalyst were characterized using XRD and SEM.The experimental results showed that the activity increased until reached a maximum,and then decreased with the increasing heating rate of calcination precursors;the photocatalytic activity decreased drastically with the fast cooling rate of calcination products.Moreover,the optimal values of calcination temperature and calcination time were obtained.As a result,the CaTiO3catalysts with high photocatalytic activity can be obtained under an optimized calcination conditions after loading CoO(0.2 wt%)co-catalyst.