Twenty-eight people, including the driver, were on the bus at the time of the crash, police said.
Authorities have not identified the victims and would not confirm whether they were players or coaches.
"Our thoughts and prayers are extended to the families of our staff and athletes as well as to all who have been impacted by this horrible tragedy," Kevin Garinger, the team's president said in a statement. "Our Broncos family is in shock as we try to come to grips with our incredible loss."
The team was scheduled to play Friday. The team lost in triple overtime to the Nipawin Hawks on Wednesday night.
Canadian Prime Minister Justin Trudeau tweeted his condolences to the victims of the crash.
Michelle Straschnitzki, who lives in Airdrie, said her 18-year old son Ryan had been taken to hospital in Saskatoon.
"We talked to him, but he said he couldn't feel his lower extremities so I don't know what's going on," she told Canadian Press. "I am freaking out. I am so sad for all of the teammates and I am losing my mind."
Darren Opp, president of the Nipawin Hawks, said a semi T-boned the players’ bus.
“It’s a horrible accident, my God,” he told the Canadian Press. “It’s very, very bad.
“It’s terrible. It’s absolutely terrible.”
An online fundraising campaign set up for family members of the team had raised more than $60,000 early Saturday.