Dwight Loomis (July 27, 1821 - September 17, 1903) was a United States Representative from Connecticut. He was born in Columbia, Connecticut where he attended the common schools. He also attended the academies in Monson, Massachusetts and Amherst, Massachusetts. He taught school and was also graduated from the law department of Yale University in 1847. He was admitted to the bar the same year and commenced practice at Rockville, Connecticut.
Loomis was a member of the Connecticut House of Representatives in 1851 and a delegate to the Republican National Convention in 1856. In addition, he was a member of the Connecticut Senate 1857-1859. Later, he was elected as a Republican to the Thirty-sixth and Thirty-seventh Congresses (March 4, 1859-March 3, 1863). While in Congress, he served as chairman, Committee on Expenditures in the Department of the Treasury (Thirty-sixth Congress). He was not a candidate for renomination in 1862. After Congress, he served as judge of the Superior Court of Connecticut 1864-1875 and a Justice of the Connecticut Supreme Court 1875-1891. He moved to Hartford, Connecticut in 1892 and was Connecticut referee from 1892 until his death in a train accident near Waterbury, Connecticut in 1903. He was buried in Grove Hill Cemetery, Rockville, Connecticut.