After practicing as a chartered accountant, Louie decided to join his family business in 1972. In 1903, Louie’s grandfather, who had immigrated to Canada from China, founded a general store in Vancouver. He was eventually named Chairman and Chief Executive Officer of London Drugs in 1998.

In 2002, Louie replaced Evaleen Jaager Roy as Chair of the Simon Fraser University Board of Governors. A few years later, in 2005, Louie was appointed chancellor of Simon Fraser University (SFU).

In 2009, Louie was made a Member of the Order of British Columbia.

As CEO and Chairman, Louie also oversees the Tong and Geraldine Louie Family Foundation and the London Drugs Foundation. In 2010, he was appointed Chairman of Grosvenor Americas Board of Directors.

In 2012, he was inducted into the Canadian Business Hall of Fame. The following year, the University of Victoria honoured him as a Distinguished Entrepreneur. A few years later, he was the recipient of the EY Family Business Award of Excellence. In 2016, he was the recipient of an honorary degree from UBC.