Joseph Ewing McDonald (August 29, 1819 - June 21, 1891) was a United States Representative and Senator from Indiana. Born in Butler County, Ohio, he moved with his mother to Montgomery County, Indiana in 1826 and apprenticed to the saddlerâ€™s trade when twelve years of age in La Fayette, Indiana. He attended Wabash College, (Crawfordsville) and graduated from Asbury University (Greencastle, Indiana; now DePauw University) in 1840. He studied law in La Fayette and was admitted to the bar in 1843, after which he practiced. He was prosecuting attorney from 1843 to 1847 and in the latter year moved to Crawfordsville where he practiced law until 1859.
McDonald was elected as a Democrat to the Thirty-first Congress, serving from March 4, 1849 to March 3, 1851. He was not a candidate for renomination in 1850, and was elected attorney general of Indiana in 1856 and was reelected in 1858. He moved to Indianapolis in 1859, was an unsuccessful candidate for Governor of Indiana in 1864, and was elected to the United States Senate and served from March 4, 1875, to March 3, 1881. He was an unsuccessful candidate for reelection. While in the Senate he was chairman of the Committee on Public Lands (Forty-sixth Congress).
McDonald died in Indianapolis in 1891; interment was in Crown Hill Cemetery.