The latest sanctions were Canada's first against Syria and Mr Assad since 2014 when a conservative government was in office.
Mr Assad, his family, government and the Syrian military hierarchy have long been the targets of sanctions.
But the government of Prime Minister Justin Trudeau extended the sanctions to 27 additional high-ranking regime officials, said Canadian Foreign Minister Chrystia Freeland.
Among them were three generals - Adib Salameh, Jawdat Salbi Mawas and Tahir Hamid Khalil - accused of ordering attacks on civilian targets and torturing regime opponents.
"Last week's chemical weapons attack in southern Idlib is a war crime and is unacceptable. Canada is working with its allies to end the war in Syria and hold those responsible to account."
Since November 2015, the Trudeau government has taken in 40,000 Syrian refugees.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
Get the latest election news, live updates and election schedule for Lok Sabha Elections 2019 on ndtv.com/elections. Like us on Facebook or follow us on Twitter and Instagram for updates from each of the 543 parliamentary seats for the 2019 Indian general elections.