The utility model provides an on -vehicle toxicity filtering ventilation system, include the system monitoring terminal and respectively with system monitoring terminal connection's on -vehicle toxicity filtering ventilation unit, on -vehicle new trend shut -off valve and on -vehicle superpressure measurement and control device, the utility model discloses dust in can effectual filtered air, the particulate matter, toxic smoke, the poisonous substance, biological microorganism and dust borne radioactivity, it is vapo(u)rish persistent agent and industry hazardous gas to adsorb simultaneously, on -vehicle new trend shut -off valve can be under the condition that on -vehicle toxicity filtering ventilation system did not use, prevent dust and wet into toxicity filtering ventilation unit in the air, the inside gas particulate filter's of extension toxicity filtering ventilation unit life, the superpressure sensor can real -time detection car under -deck the pressure data and transmit to the superpressure valve, the aperture of control superpressure valve changes, make cockpit be in the environment of a malleation, prevent that outside hazardous gas from flowing in the car under -deck.