Thin copper films with grain sizes of 31 nm and 3.3 mu m were processed by electrodeposition, and their mechanical properties were compared with those of a rolled copper film. The hardness and strength for the electrodeposited copper with a grain size of 3.3 Pm were lower than those of the rolled copper with a grain size of 6.3 mu m, however, the elongation to failure for the former was larger than that for the latter. Intense (111) texture formation was found for the rolled copper. Therefore, it is suggested that the difference in mechanical properties between the electrodeposited and rolled copper films are related to the texture formation. The electrodeposited copper with a grain size of 31 nm showed higher strength and larger elongation than the rolled copper. The very small grain size of 31 nm gave rise to the excellent mechanical properties.