The invention discloses a high-frequency isolation transformer which comprises an armored high-voltage cable and a plurality of magnetic rings; the armored high-voltage cable comprises an inner conductor and an inner insulating layer, a shielding layer, an outer insulating layer, an armor layer and a rubber outer sheath which sequentially coat the outside of the inner conductor; the plurality of magnetic rings tightly sleeve the rubber outer sheath of the armored high-voltage cable; secondary parts of the transformer are formed at both ends of the inner conductor, and the both ends of the inner conductor are connected with an output end of a secondary part of an insulating connector; both ends of the shielding layer and the armor layer are connected to form a primary part of the transformer, and the both ends of the shielding layer and the armor layer are respectively connected with an input end of a primary part of the insulating connector. According to the high-frequency isolation transformer disclosed by the invention, by effective structural design, a radio frequency transmitter of a radio frequency ion source, a coil at a high-potential end on the radio frequency ion source, and the like are isolated, and by using a conventional high-voltage cable as a main body structure, the machining and manufacturing difficulty is simplified, and cost is reduced.