| Homer Augustus Nelson | |
| Image Name: | Homer A Nelson.jpg |
| State: | New York |
| District: | 12th |
| Party: | Democrat |
| Term: | March 4, 1863 - March 3, 1865 |
| Preceded: | Stephen Baker |
| Succeeded: | John Henry Ketcham |
| Office2: | New York Secretary of State |
| Term Start2: | January 1, 1868 |
| Term End2: | December 31, 1871 |
| Governor2: | Reuben Fenton John T. Hoffman |
| Predecessor2: | Francis C. Barlow |
| Successor2: | G. Hilton Scribner |
| Office3: | Member of the New York State Senate |
| Term Start3: | January 1, 1882 |
| Term End3: | December 31, 1883 |
| Predecessor3: | Stephen H. Wendover |
| Successor3: | Thomas Newbold |
| Birth Date: | August 31, 1829 |
| Birth Place: | Poughkeepsie, New York, U.S. |
| Death Place: | Poughkeepsie, New York, U.S. |
| Spouse: | Helen Stearns |
| Profession: | Politician, lawyer |
| Resting Place: | Poughkeepsie Rural Cemetery |
Homer Augustus Nelson (August 31, 1829 - April 25, 1891) was an American politician and soldier from the state of New York. He served one term in the U.S. House of Representative and was an officer in the Union Army during the first part of the Civil War and a United States congressman during the latter half of the war.
Nelson was born in Poughkeepsie, New York, where he was also raised and educated. He studied law and was admitted to the bar, commencing practice in Poughkeepsie.
He was a judge of Dutchess County, New York, from 1855 to 1862.
At the outbreak of the Civil War, he became colonel of the 159th New York Volunteer Infantry.
He left in 1863 when he took his seat in the 38th United States Congress, but was unsuccessful for reelection in 1864.
Following the war, he was a delegate to the New York State Constitutional Convention in 1867 and the same year was elected Secretary of State of New York serving until 1871. He was a member of the New York State Senate (15th D.) in 1882 and 1883; and was appointed to the commission to report a revision of the judiciary article of the New York Constitution in 1890.
He died on April 25, 1891, in Poughkeepsie and was interred in Poughkeepsie Rural Cemetery.