| W. D. Lyon | |
| Office: | Member of the Tennessee House of Representatives from Sullivan County |
| Term Start: | January 2, 1905 |
| Term End: | January 7, 1907 |
| Preceded: | W. M. Poe |
| Succeeded: | J. Parks Worley |
| Term Start2: | January 7, 1901 |
| Term End2: | January 5, 1903 |
| Preceded2: | Jack Faw |
| Succeeded2: | W. M. Poe |
| Birth Name: | William David Lyon |
| Birth Date: | 21 February 1864 |
| Death Place: | Bluff City, Tennessee, U.S. |
| Party: | Democratic |
| Spouse: | |
William David Lyon (February 21, 1864 – July 30, 1947) was an American politician who served two terms in the Tennessee House of Representatives.[1]