The invention discloses a corona discharging ion source assembly and an ion implantation method thereof. The corona discharging ion source assembly comprises an insulation sleeve, an ion generation cavity is constructed in the insulation sleeve, an opening communicated with the ion generation cavity is formed at a bottom end of the insulation sleeve, and the insulation sleeve is provided with an air supply channel communicated with the ion generation cavity; an ion reaction chamber, the ion reaction chamber is constructed by an insulation member, an ion reaction cavity is constructed in the ion reaction chamber, and the opening and the ion reaction cavity are communicated; a corona discharging needle assembly, the corona discharging needle assembly can be adjustably stretched into the ion generation cavity through an upper end of the insulation sleeve, and the corona discharging needle assembly and a corona discharging net are spaced; an ion implantation electrode, the ion implantation electrode is arranged on the ion reaction chamber, and the ion implantation electrode and the corona discharging net are spaced; and a controller, the controller is connected with a corona discharging high voltage power source and the ion implantation electrode. The corona discharging ion source assembly is advantaged in that valid ions are enhanced, an ion implantation rate is improved, and discharging is more stable.