The present invention discloses a positive and negative ion source based on radio-frequency inductively coupled discharge, comprising a tube, a middle portion of which is communicated with an intake pipe; discharge coils electrically connected to a matched network and a radio-frequency power supply successively are wound on the tube; one end of the tube is connected to a first cover plate in a sealed manner, and the first cover plate is connected with a positive ion extraction gate via an insulating medium; the positive ion extraction gate is electrically connected to a negative pole of a DC power supply; the other end of the tube is connected to a second cover plate in a sealed manner, the second cover plate is connected to a third cover plate in a sealed manner via a sidewall, and the third cover plate is connected with a negative ion extraction gate via an insulating medium; and the negative ion extraction gate is electrically connected to a positive pole of the DC power supply. In the present invention, the positive ions and the electrons and negative ions can be extracted simultaneously, and the problems of contamination of the ion source by particles sputtered from the backplane and overheating of the backplane are thus solved.