The invention discloses a paint spraying wastewater treatment device. The paint spraying wastewater treatment device includes an automatic control system, a water pump system, a dosing device, a pretreatment tank, an oxidation device, a reaction tank, a coagulation and flocculation tank, a sedimentation tank and a filter pressing device, wherein the pretreatment tank, the oxidation device, the reaction tank, the coagulation and flocculation tank, the sedimentation tank and the filter pressing device are sequentially connected, the pretreatment tank, the oxidation device, the reaction tank, the coagulation and flocculation tank, the sedimentation tank, the filter pressing device and the water pump system are electrically connected with the automatic control system, PH meters capable of detecting PH values are arranged in both the pretreatment tank and the reaction tank, an ultraviolet lamp and a stirring device capable of performing mechanical stirring are arranged in the oxidation device, the pretreatment tank, the oxidation device, the reaction tank and the coagulation and flocculation tank are connected with the dosing device capable of adding chemicals, and a mud pressing machine is arranged at the bottom of the filter pressing device. The paint spraying wastewater treatment device adopts the ultraviolet lamp and a Fenton oxidation technology combined treatment method and is matched with the corresponding oxidation device to conduct automatic oxygenolysis treatment on paint spraying wastewater, so that the removal rate of COD in the paint spraying wastewater can be 80% or above.