Abnormal grain growth in thin Cu films on Si substrates has been investigated as a function of annealing time. Abnormal grains with(1 1 0) orientation were observed by transmission electron microscopy. X-ray diffraction patterns showed that the films which underwent extensive abnormal grain growth also underwent a change in texture from (1 1 1) to (1 0 0), (1 1 0) and (3 1 1). A simple theoretical analysis showed that these were the results of a strain-energy-driven abnormal grain growth process.