The invention provides a fresh air processing device. The fresh air processing device comprises a box body (10) and a flow choking device (20), wherein the box body (10) comprises a first air inlet (11), a first air outlet (12) and a fresh air passage which communicates with the first air inlet (11) and the first air outlet (12); the flow choking device (20) is arranged on the fresh air passage and is used for choking water vapor or rain. By adopting the fresh air processing device disclosed by the invention, the problem that the fresh air processing device in the prior art is poor in waterproofness can be solved.