In this work, epitaxial Ge films grown on Si by magnetron sputtering were annealed by diode laser as a replacement for conventional thermal annealing to reduce the threading dislocation density (TDD). After laser scans of millisecond exposure time, improvement of crystallinity and increase in tensile strain are observed in the Ge films. TDD of the Ge film is reduced by two orders of magnitude from 10(10) cm(-2) to 10(8) cm(-2) after only three laser scans. Diode laser annealing is a fast and low-cost method to effectively reduce TDD in epitaxial Ge films on Si. (C) 2016 Elsevier B.V. All rights reserved.