The present invention discloses a USB charger multichannel testing device with a micro USB. The USB charger multichannel testing device with the micro USB comprises a pedestal, a USB plug positioning module, an AC thimble positioning module, a product pallet and a pallet pedestal. Each pair of AC thimbles adaptively corresponds to the USB plug arrangement, and the USB positioning module is configured to allow a plurality of USB plugs to apply USB chargers with different heights and different directions; the product pallet capable of disposing a plurality of chargers to be tested is able to be detachably stuck on the pallet pedestal, and the product pallet is directly taken out to be disposed on the product pallet pedestal after a forepart test is end, so that time of repeatedly dismounting dischargers is avoided; and the product groove of the product pallet is designed according to the size and the model of products, and the positions of the AC thimbles are changed with the variation of the fixture position of the AC thimble regulation device in a second regulation hole. The USB charger multichannel testing device with a micro USB is applicable to the detection of a plurality of chargers with specifications, is convenient to use, high in versatility, fast in detection speed and high in safety. The present invention further discloses an application method of a SB charger multichannel testing device with a micro USB.