Oscar E. Hailey (December 10, 1870 – July 5, 1958) was a Republican politician from Idaho. He served on two occasions as the 16th and 18th Lieutenant Governor of Idaho, both during the administration of Governor H. C. Baldridge.Hailey was elected in 1926 along with Baldridge. He was succeeded as the Republican nominee in 1928 by W. B. Kinne, but returned to the position in October 1929 after Kinne died in office.Hailey also served in the Idaho Legislature.