| William Watson | |
| Birth Date: | 14 March 1858 |
| Birth Place: | Garston, Liverpool |
| Death Date: | 30 January 1925 |
| Death Place: | St Albans, Hertfordshire, UK |
| Citizenship: | United Kingdom |
| Fields: | botany |
| Workplaces: | Royal Botanical Gardens at Kew |
| Author Abbrev Bot: | W.Watson |
William Watson (1858–1925) was a British botanist and horticulturist. He was a gardener at the Royal Botanic Gardens, Kew from 1879, Assistant Curator 1886–1901 and Curator 1901–1922. Watson was awarded the Veitch Memorial Medal in 1892 and elected as an Associate of the Linnean Society in 1904.
The species Hebenstretia watsonii was named in his honour.