The invention discloses an oxidative pyrolysis process of dinitrotoluene wastewater. The oxidative pyrolysis process comprises the following steps of: passing wastewater from a washing kettle through a buffer tank, a settling tank, a preheater, a high pressure pump, a pyrolytic preliminary heat exchanger, a pyrolytic hot oil heat exchanger, a pyrolysis reactor, a pyrolysis cooler and a buffer tank to be discharged, wherein an oxidant is added at an inlet of the settling tank and/or the pyrolytic preliminary heat exchanger; and the oxidant is added into the pyrolytic preliminary heat exchanger through pressurization. According to the process, the chromaticity of the wastewater processed by the oxidative pyrolysis process is reduced by 25-30 percent in comparison with the conventional process, the scaling in the heat exchanger of the system can be effectively reduced, the operation cost can be reduced, and the content of aromatic nitro compounds (dinitrotoluene, nitrocresol and the like) in the wastewater after treatment is reduced by 25-30 percent compared with that in the conventional process.