The invention relates to a preparation method of a photocatalytic material titanium (Ti)-doped bismuth oxychloride (BiOCl) microsphere. The method comprises the following steps: dispersing bismuth nitrate pentahydrate into an organic solvent, and performing uniform stirring to form a stable solution; slowly adding sodium chloride and tetrabutyl titanate into the stable solution under ultrasonic conditions, performing uniform mixing, pouring into a stainless steel reaction kettle with a polytetrafluoroethylene liner, and performing natural cooling for 8 to 24h at the temperature of 160 to 200 DEG C; centrifugally washing a reaction product for many times by using deionized water and absolute ethyl alcohol, and performing drying to obtain the Ti-doped BiOCl microsphere, wherein the doped molar weight is 0.5:1 to 1:1. The preparation method is simple in preparation process and high in reaction controllability. The photocatalytic activity of the prepared material is higher than that of single BiOCl, a high-concentration dye wastewater Rhodamine B solution can be effectively treated, and the prepared material plays a potential application role in environmental management, particularly, high-concentration fuel wastewater pollution treatment.