The invention discloses a vertical-ring magnetic separator for de-ironing of pulverized coal ash. The vertical-ring magnetic separator comprises a rotating ring, an induction medium, an upper iron yoke, a lower iron yoke, an exciting coil, a feeding opening, a tailing bucket and a water washing device, wherein the induction medium is arranged in the rotating ring. The exciting coil is arranged at the periphery of the upper iron yoke and the lower iron yoke, so as to lead the upper iron yoke and the lower iron yoke to become a pair of magnetic poles for generating a magnetic field in the vertical direction. The upper iron yoke and the lower iron yoke are respectively arranged at the inner and outer sides below the rotating ring. The induction medium is layers of steel plate meshes, each steel plate mesh is woven by wire peduncles, and ridge-shaped sharp corners are arranged at the edges of the wire peduncles. The upper iron yoke is connected with the feeding opening, the lower iron yoke is connected with the tailing bucket for discharging, and the water washing device is arranged above the rotating ring. By adopting the vertical-ring magnetic separator in the invention, the de-ironing effect is improved by 20%, and the effective de-ironing rate is increased to 80% from 60%; moreover, the pressure for de-ironing of solution in the subsequent process is relieved, the production cost is reduced, and the production efficiency is increased.