Researchers say firearms either kill or injure a child or youth almost every day in Ontario.
Their study, published in today's Canadian Medical Association Journal, found there were an average 355 firearm injuries each year among children and youth.
They compiled the date by analyzing hospital records of millions of Ontario children.
One of the study's authors, Dr Astrid Guttmann of Toronto's Hospital for Sick Children, says three quarters of the gunshot wounds were unintentional.
The study found Canadian-born youth had the highest rates of unintentional firearm injury, but when it came to assaults or intentional shootings, immigrants and refugees were at much higher risk than non-immigrant children.
One of the study's other authors says there has been little Canadian research on children harmed by firearms.
Dr Natasha Saunders, also of Sick Kids hospital, says it's hoped the study will lead to greater efforts to reduce firearm deaths amongst young people.