He will also be the first sitting prime minister to march in a pride parade.
Justin Trudeau kicked off Pride Month in Canada by raising a pride flag on Parliament Hill for the very first time.
Adrian Wyld / THE CANADIAN PRESS
He was joined by MPs from all the other parties for the occasion.
"It's not just Liberals who are here," Trudeau said. "We have Conservatives here. We have NDP here. We have Bloq Quebecois and Green Party members here."
Adrian Wyld / THE CANADIAN PRESS
Trudeau will also mark another milestone this year when he becomes the first sitting prime minister to march in Canadian pride parades.
The prime minister said there was "more work to do" on LGBTQ rights, and cited his government's bill to expand human rights legislation to trans people.
The trans pride flag was hung alongside the maple leaf in the House of Commons foyer for the first time ever when the government announced the trans rights bill a couple of weeks ago.
Adrian Wyld / THE CANADIAN PRESS
"Canada is united in its defence of rights, in its standing up for LGBTQ rights. This is what we are truly celebrating today."
Adrian Wyld / THE CANADIAN PRESS