The invention provides a compact high-isolation antenna, which comprises a printed circuit board. An annular ground radiation antenna is arranged on the printed circuit board; a monopole antenna is arranged above the annular ground radiation antenna; the annular ground radiation antenna comprises a clearance zone arranged on the printed circuit board and a metal conduction strip arranged in the clearance zone and connected with a non-clearance zone on the printed circuit board; the monopole antenna comprises a feed arm and a radiation arm; one end of the feed arm is connected with a first feed source of the printed circuit board, and the other end is connected with the radiation arm; and the feed arm is located in a range above the printed circuit board corresponding to the clearance zone. The antenna of the invention combines the annular ground radiation antenna and the symmetric-arm monopole antenna together, the feature of orthogonal radiation current of the two is used, high isolation can be realized in a condition in which positions of the two antennas coincide, the structure is simple, changes are diverse, and effects of realizing the best isolation are better.