Galen Weston is a graduate of the University of Western Ontario. He and his family are the second richest family in Canada, with a net worth of US$8.4 billion, and the 59th richest family in the world (according to Forbes[1]. His family's fortune comes from their interest in such stores as Loblaws, Holt Renfrew, and Selfridges. Following the death of his brother Garry Weston, Galen's interests have again spread to the United Kingdom, against the unwritten pact which followed the division of their father's assets into the British/European enterprises, notably Associated British Foods, controlled by Garry, the North American bakeries George Weston Limited controlled by Galen, and the US interests controlled by eldest brother Grainger. Their six sisters received nothing.

Galen Weston is married with two children, Galen Jr. and Alannah. His wife Hilary (born Hilary Frayne in Dublin in 1942) served as the 26th Lieutenant Governor of Ontario from 1997 to 2002.

Alannah Weston, his daughter, was appointed as Creative Director of British retailer Selfridges, purchased by Galen Weston's holding company in 2003.

In 1990, he was made an Officer of the Order of Canada. In 2005, he was awarded the Order of Ontario.