The invention provides an antenna system, comprising a sub-array horn unit, wherein the sub-array horn unit comprises a metal base provided with a back cavity; The circuit board comprises a circuit board main body and four rectangular slots running through the circuit board main body, wherein the four slots are arranged staggered and surrounded to form a central region; the circuit board is connected with the top surface of the metal base and completely covers the back cavity. The slot forms a feeding port of the sub-array horn unit; A phase shifting unit electrically connected to the circuitboard and located in the central region is superposed. The horn unit comprises four horns superposed and electrically connected to the circuit board, four horns are connected end to end in turn and annularly arranged on the phase shifting unit, and each horn is press-fitted on a slot. The invention also provides a communication terminal. Compared with the related art, the antenna system and the communication terminal of the invention have strong and stable communication signal, good reliability and wide frequency band coverage.