Breathable student's backpack

The invention provides a breathable student's backpack. Vent passages are formed among protrusions to facilitate air ventilation and circulation for the human back easily sweating and to keep dry; when an elastic airbag is under pressure from the human back, air in the elastic airbag will pass through a breathable waterproof layer through third through holes and then passes sequentially through fourth through holes and fifth through holes to blow on the human back, improving air flow speed at the human back and providing better cooling and comfort, and since the first through holes and the second through holes are fitted with one-way intake valves, air in the elastic airbag can be discharged from all of the third through holes, the fourth through holes and the fifth through holes, ensuring blowing efficiency for the human back; when the elastic airbag is not under pressure, the elastic airbag blows up fast under auxiliary action of self-elasticity and elasticity of pressure springs, external air will passes through the breathable waterproof layer via the second through holes and is then quickly sucked into the elastic airbag through the first through holes and the one-way intake valves, and the elastic airbag can repeat such breathing cycle by serving as an elastic breathing power source.