| Honorific-Prefix: | The Honourable |
| Lionel Herbert Clarke | |
| Order: | 12th |
| Office: | Lieutenant Governor of Ontario |
| Term Start: | November 20, 1919 |
| Term End: | August 29, 1921 |
| Predecessor: | Sir John Strathearn Hendrie |
| Successor: | Henry Cockshutt |
| Governor General: | The Duke of Devonshire The Lord Byng of Vimy |
| Premier: | Ernest Charles Drury |
| Birth Date: | 20 July 1859 |
| Birth Place: | Guelph, Canada West |
| Death Place: | Toronto, Ontario, Canada |
| Nationality: | Canadian |
| Alma Mater: | Trinity College School University of Edinburgh |
| Occupation: | Brewer, businessman |
Lionel Herbert Clarke (July 20, 1859 - August 29, 1921) was a Guelph-born businessman and the 12th Lieutenant Governor of Ontario, Canada. In 1911, he was appointed the first chairman of the Toronto Harbour Commission
The son of William Clarke and Clara Piggott Strange, he was educated in Port Hope. In 1891, Clarke married Anne Clara Gertrude Small.
In 1893, Lionel partnered with "barley king" Wilmot Deloui Matthews as L. H. Clarke and Company, malt dealers, then in 1900 they established the Canada Malting Company Limited of which Clarke became president in 1908.
Clarke was appointed lieutenant governor November 20, 1919. Diagnosed with stomach cancer, Clarke died at Government House, Toronto. After a state funeral, he was buried in Mount Pleasant Cemetery, Toronto.
Dictionary of Canadian Biography Online http://www.biographi.ca/EN/009004-119.01-e.php?id_nbr=8078