The present disclosure provides an antenna system including an antenna assembly embedded in a grounding foundation plate. The antenna assembly includes a first printed circuit board, a second printed circuit board, a third printed circuit board, a first conductive layer, a feed sheet, a second conductive layer, a first radiation gap disposed in the second conductive layer, and a second radiation gap disposed in the second conductive layer. The antenna assembly further includes a feed point disposed at one end of the feed sheet for electrically connecting to an external circuit and transferring the power to the second conductive layer via the feed sheet, by which, the first radiation gap works at a first frequency band, and the second radiation gap works at a second frequency band. Both of the first and second frequency bands are included in 5G frequency bands.