She replaces Ernie Hardeman who served as agriculture minister under two premiers.
Premier Doug Ford made more than a dozen cabinet changes late Friday, the most notable being the return of former Finance Minister Rod Phillips who resigned after taking an overseas vacation during the COVID-19 lockdown and ban on international travel.
Phillips takes over from Merilee Fullerton at the ministry in charge of long-term care homes where hundreds died in horrific conditions during the pandemic.
Fullerton has been moved to children and family services.
Thompson was first elected in 2011 and was opposition critic for environment, for energy and then small business and red tape and then indigenous affairs and international trade.
When Ford won in 2017, she became education minister, then Minister of Government and Consumer Services.
