The present invention provides a method for producing Cu67 radioisotope suitable for use in medical applications. The method comprises irradiating a metallic zinc-68 (Zn68) target with a high energy gamma ray beam. After irradiation, the Cu67 is isolated from the Zn68 by any suitable method (e.g., chemical and/or physical separation). In a preferred embodiment, the Cu67 is isolated by sublimation of the zinc (e.g., at about 500-700° C. under reduced pressure) to afford a copper residue containing Cu67. The Cu67 can be further purified by chemical means (i.e., dissolution in acid, followed by ion exchange).