The fatal crash, which also injured 10 people including the truck driver, happened Monday in the heart of Glasgow during the height of Christmas shopping.
Media reports say Jack Sweeney, 68, his wife Lorraine, 69, and their 16-year-old granddaughter Erin McQuade were among the shoppers.
The three were identified as being from Dumbarton, Scotland, but media reports identified Jack Sweeney as a former president of the Bramalea Celtic Club in Brampton, Ont., northwest of Toronto.
A statement posted on the soccer supporters' club Facebook page said: "It is with great shock and sadness we share with you our friend and past president Jack Sweeney, his wife Lorraine and granddaughter Erin were victims of today's tragedy in Glasgow."
"Our thoughts and prayers go to the family and friends of the Sweeney family."
Police have said the truck driver lost control of the vehicle Monday afternoon before hitting a number of pedestrians. Six people remained hospitalized Tuesday.