Incomplete absorption of antibiotics leads to environmental damage, which has aroused strong and urgent attention. To solve this problem, in this paper, we first proposed oxygen vacancy (OVs) and Zn ion doping synergy BiOBr (Zn-VBOB) photocatalyst. The results show the degradation rate constants of Zn-VBOB for carbamazepine (CBZ) and sulfamethoxazole (SMX) were 10.15 and 2.5 times higher than that of undoped BiOBr, respectively, and higher than the single Zn-doped or OVs involved ones. Zn-VBOB can generate more types of radicals as the degradation active species in comparison of the single Zn or OVs introduced ones in which the mechanism was systematically studied by radical capture experiment and DFT calculation.