| Henri-Raymond Casgrain | |
| Birth Date: | 16 December 1831 |
| Birth Place: | Rivière-Ouelle, Lower Canada |
| Death Place: | Quebec City, Quebec |
| Relations: | Charles-Eusèbe Casgrain, father |
| President of the Royal Society of Canada | |
| Term: | 1889–1890 |
| Predecessor: | Sandford Fleming |
| Successor: | George Monro Grant |
Henri-Raymond Casgrain (December 16, 1831 - February 11, 1904) was a French Canadian Roman Catholic priest, author, publisher, and professor of history.
Born in Rivière-Ouelle, Lower Canada, the son Charles-Eusèbe Casgrain and Eliza Anne Baby, Casgrain studied at College of Sainte-Anne-de-la-Pocatière. In 1852, he enrolled in the Montreal School of Medicine and Surgery, but became a priest in 1856. He started teaching at the College of Sainte-Anne-de-la-Pocatière until he was forced to give up teaching because of ill health. In 1859, he was appointed curate of the parish of La Nativité-de-Notre-Dame at Beauport and was free to devote himself entirely to literary pursuits.
In 1877, he was awarded a doctorate of history from the Universite Laval, where he would remain as professor.
He wrote primarily on New France and its personalities, such as Samuel de Champlain, Louis-Joseph de Montcalm and his aide-de-camp Francis de Gaston, Chevalier de Levis.
From 1889 to 1890, he was the president of the Royal Society of Canada.