The invention discloses a chemical sewage treatment device with an ozone sterilization harmful gas treatment function. The chemical sewage treatment device comprises a chemical sewage inlet, a sewage adapter, a water amount control valve, a water inlet pipeline, a sewage filtering device, a first rotator, a first filter, a second filter, a sewage transition pipeline, an ozone sterilization device, a sewage detector, an internal circulation reactor, an ozone generator, a second rotator, a water outlet pipeline and a water outlet pipeline interface, wherein the water inlet pipeline is connected with the sewage filtering device; the right side of the sewage filtering device is connected with the ozone sterilization device through the sewage transition pipeline; the internal circulation reactor and the ozone generator are arranged in the ozone sterilization device. The chemical sewage treatment device with the ozone sterilization harmful gas treatment function has more complete filtering and sterilizing effects; the working efficiency of the device is increased greatly, and higher filtering efficiency is achieved; moreover, the device is more stable in structure, is prevented from being damaged, can be used for a longer time, and is more stable in operation.