Official Opposition Canada portal The 40th Legislative Assembly of Ontario was a legislature of the government of the province of Ontario, Canada.

The membership was set by the 2011 Ontario general election.

The government was led by Premier Dalton McGuinty until his resignation resulted in the 2013 leadership election, which selected Kathleen Wynne as his successor.

The Official Opposition was the Progressive Conservative Party, led by Tim Hudak, and the third party was the New Democrats, led by Andrea Horwath.

On May 2, 2014, Premier of Ontario Kathleen Wynne announced that she had formally requested that Lieutenant Governor of Ontario David Onley dissolve the 40th Legislative Assembly of Ontario and call a provincial general election to occur on June 12, 2014.