| Office: | President of the West Virginia Senate |
| Term Start: | 1869 |
| Term End: | 1871 |
| Governor: | William E. Stevenson |
| Predecessor: | William E. Stevenson |
| Successor: | Lewis Baker |
| Order2: | 2nd |
| Office2: | Governor of West Virginia |
| Term Start2: | February 26, 1869 |
| Term End2: | March 4, 1869 |
| Predecessor2: | Arthur I. Boreman |
| Successor2: | William E. Stevenson |
| Birth Name: | Daniel Duane Tompkins Farnsworth |
| Birth Date: | December 23, 1819 |
| Birth Place: | Staten Island, New York |
| Death Place: | Buckhannon, West Virginia |
| Spouse: | Mary Ireland Farnsworth |
| Profession: | Politician |
| Party: | Republican |
Daniel Duane Tompkins Farnsworth (December 23, 1819 – December 5, 1892) was an American politician in the U.S. state of West Virginia, who served in the West Virginia Senate and briefly as the second Governor of West Virginia.
Farnsworth was born in Staten Island, New York. When he was two, his family relocated to Buckhannon, West Virginia in Upshur County. He married Mary Ireland.[1] Farnsworth was the President of the West Virginia Senate in 1869 when Governor Arthur I. Boreman vacated his office to serve in the United States Senate. Farnsworth then served as Governor of West Virginia for seven days, from February 26, 1869 - March 4, 1869.