The invention relates to a treatment method for improving removal rate of benzo (a) pyrene in coking wastewater. The method is characterized by comprising the following steps of: (1) conveying the coking wastewater into an oil separation tank, and removing suspension oil in water; (2) conveying the wastewater from the oil separation tank into an air floatation reactor, adding a coagulant, a coagulant aid and a demulsifier into the air floatation separation reactor; (3) conveying the effluent of the air floatation separation reactor into an A2/O biological treatment process; (4) conveying the effluent of the biological treatment process into a coagulation sedimentation basin, adding the coagulant and the coagulant aid into the coagulation sedimentation basin; (5) conveying the effluent of the coagulation sedimentation basin into an active carbon filtering basin. The method has the advantages that the air floatation and turbidity removal procedures are strengthened based on the distribution characteristics of the benzo (a) pyrene which mostly forms solid suspension or is dissolved in oil, removal of benzo (a) pyrene in coking wastewater is efficient, and the increasingly stringent wastewater treatment and discharge requirements are met.