The invention discloses a flameout system of a vehicle during exhaust brake. The flameout system comprises a fuel tank, a filter, a hydraulic pump, a gear choosing operating valve, a forward gear clutch, a first one-way valve, an air bag, an exhaust butterfly valve switch, a flameout switch, a pneumatic control valve, a hydraulic control air valve, a flameout cylinder, an exhaust butterfly valve, a second one-way valve, a backward gear clutch and a butterfly valve cylinder, wherein the gear choosing operating valve comprises an operating lever; and the operating lever is connected with a gear selector positioned in a cab through a flexible shaft. According to the flameout system of the vehicle during exhaust brake, the drying safety is high, the vehicle can automatically flame out during exhaust brake.