A plasma air purifying device includes a container and at least one plasma-generating element. The container includes a container body, a plurality of first partition plates and a plurality of second partition plates. The container body has an air inlet, an air outlet, and an accommodating space between the air inlet and the air outlet, and the accommodating space includes a plasma zone and a reaction zone. The first partition plates and the second partition plates are staggered in the reaction zone to separate a plurality of reaction chambers. The reaction chambers integrate spatially first through channels of the corresponding first partition plates and second through channels of the corresponding second partition plates so as to form a repetitive bending reaction channel, such that the plasma can purify the air flowing through the air inlet, the plasma zone, the repetitive bending reaction channel and the air outlet.