The utility model discloses a full-automatic air microbe sampler comprising a sample collecting system and a sample liquid distribution system, wherein the sample collecting system comprises a sampling head, a blower, an impact sampling bottle, a liquid storage bottle, an injection pump and a sampling pump; two outlets of the sampling head are communicated with the blower and the impact sampling bottle respectively; the gas inlet of the sampling pump is communicated with the impact sampling bottle; the liquid storage bottle is communicated with the injection pump and the impact sampling bottle sequentially; the sample liquid distribution system comprises a peristaltic pump and an injection device; the peristaltic pump is communicated with the impact sampling bottle; and the outlet of the peristaltic pump is connected with the injection device through a pipeline. As the sampling head can adopt a two-stage virtual impact principle, the sampler has the advantages that the wall damage of a particle can be reduced, and a higher particle size cutting efficiency can be obtained. Moreover, the sampling flow rate is high; the microbe particle collection density is improved; convenience is brought for further experimental analysis; and the sensitivity and the accuracy of instrument are improved.