| William H. Douglas | |
| Birthname: | William Harris Douglas |
| Image Name: | William Douglas (Congressman).jpg |
| Office: | Member of the U.S. House of Representatives from New York |
| Constituency: | (1901–03) (1903–05) |
| Term Start: | March 4, 1901 |
| Term End: | March 3, 1905 |
| Preceded: | William A. Chanler |
| Succeeded: | J. Van Vechten Olcott |
| Birth Date: | 5 December 1853 |
| Birth Place: | New York City, New York |
| Death Place: | New York City, New York |
| Resting Place: | Sleepy Hollow Cemetery, Tarrytown, New York |
| Party: | Republican |
| Alma Mater: | City College of New York |
William Harris Douglas (December 5, 1853 – January 27, 1944) was an American businessman and politician who served two terms as a U.S. Representative from New York from 1901 to 1905.
Born in New York City, Douglas attended private schools and the College of the City of New York.He entered the exporting and importing trade business.
Douglas was elected as a Republican to the Fifty-seventh and Fifty-eighth Congresses (March 4, 1901 – March 3, 1905).
He declined to be a candidate for renomination in 1904.
He resumed his former business pursuits.He served as delegate to the Republican National Conventions in 1908, 1912, and 1916.
He died in New York City on January 27, 1944, and was interred in Sleepy Hollow Cemetery, Tarrytown, New York.