Ira Allen Eastman (January 1, 1809 – March 21, 1881) was a U.S. Representative from New Hampshire, nephew of Nehemiah Eastman.
Born in Gilmanton, New Hampshire, Eastman attended the local schools. He was graduated from Dartmouth College in Hanover, New Hampshire, in 1829. He studied and was admitted to the bar in 1832, commencing practice in Troy, New Hampshire. He returned to Gilmanton in 1834 and continued the practice of law. He served as clerk of the State house of representatives in 1835. He served as member of the State house of representatives 1836-1838, and served as speaker in 1837 and 1838. He was Register of Probate from 1836 to 1839.
Eastman was elected as a Democrat to the Twenty-sixth and Twenty-seventh Congresses (March 4, 1839-March 3, 1843). He served as chairman of the Committee on Revisal and Unfinished Business (Twenty-seventh Congress). He was not a candidate for renomination in 1842.
He served as judge of the court of common pleas 1844-1849. He served as associate judge of the supreme court 1849-1855 and as judge of the superior judicial court from 1855 to 1859. He was chosen trustee of Dartmouth College in 1859. He was an unsuccessful Democratic candidate for Governor in 1863 and for United States Senator in 1866.
He resumed the practice of law, and died in Manchester, New Hampshire, March 21, 1881. He was interred in Valley Cemetery.