The invention relates to the technical fields of water treatment and rare earth mineral recovery and discloses an organic diphosphonic acid adsorbent and application thereof as well as a method for removing erbium ions. The organic diphosphonic acid adsorbent with a structure as shown in a formula (1) and the erbium ions are contacted under the existence of a solution, and the content of the erbium ions in the solution can be reduced to 0.005 mg/L or less even if through one-time adsorption operation.