Meanwhile, Halfpenny will act as back-up to Tyrone Green, the only specialist full-back in Harlequins’ senior squad.
Since making his Wales debut in 2008, Halfpenny has become a giant of European rugby, winning 101 caps for his country and the Six Nations Grand Slam in 2012 and 2019.
He has played in three World Cups and starred in the 2013 Lions tour to Australia, where he was named Player of the Series in a 2–1 win.
Halfpenny’s move means he will play in the Premier League for the first time. He spent most of his playing career with Cardiff Rugby and Scarlets in Wales, before spending three years with Toulon in France.
“I am delighted to be joining Queens and grateful for the opportunity to continue my career at such an iconic club,” Halfpenny said.
“I have always admired the Premiership and I want to take this opportunity with both hands and contribute to the Queen’s DNA.”