A high-energy ion implanter includes a beam generation unit that includes an ion source and a mass analyzer, a high-energy multi-stage linear acceleration unit, a high-energy beam deflection unit that changes the direction of a high-energy ion beam toward a wafer, and a beam transportation unit that transports the deflected high-energy ion beam to the wafer. The beam transportation unit includes a beam shaper, a high-energy beam scanner, a high-energy beam collimator, and a high-energy final energy filter. Further, the high-energy beam collimator is an electric field type beam collimator that collimates a scan beam while performing the acceleration and the deceleration of a high-energy beam by an electric field.