Pedestrian protection device for vehicle

The invention provides a pedestrian protection device for a vehicle, which is arranged at the bottom of the vehicle, and comprises: a plurality of infrared human body sensing modules which are positioned in front of each wheel of the vehicle and generate electric signals when sensing pedestrians; a plurality of buffer air bag modules which are arranged behind the infrared human body induction module, wherein each buffer air bag module comprises a shell, a liquid nitrogen tank, a liquid nitrogen trigger and an air bag; telescopic baffle modules which are correspondingly arranged behind the buffer airbag modules, wherein each telescopic baffle module comprises a baffle shell, two sections of telescopic baffles, a lower end baffle and a baffle trigger; a main control chip which is located above the infrared human body induction module and used for generating and sending a liquid nitrogen trigger signal, a baffle trigger signal and a voice trigger signal after receiving the electric signal; a buzzer which is arra