Australian born Lovegrove, 27, has spent the past eight seasons at Hull KR and made over 160 appearances since coming to the UK from NRL side St George Illawarra in 2007.
The back row forward gained a release from the final year of his Rovers contract on compassionate grounds stating that having spent all his adult life in Hull he and his family wanted to move closer to family members, which a move to London allows.
“Rhys is another great addition to our squad for 2015 and again shows the calibre of player we are attracting with our vision for the club moving forward,” said head coach Joey Grima.
“We’ll welcome Rhys to the club for pre-season training in November as a mature and experienced player who will work well with our younger players to help develop them whilst also concentrating on his game.”
Lovegrove is excited to be joining the Broncos and is looking forward to the challenge that awaits him.
“Joining the Broncos is a great move on and off the field,” said Lovegrove. “On the field, I am excited by the new challenge of helping the Broncos regain Super League status, while continuing to promote and develop rugby league in the capital city. Head coach Joe Grima sold the club superbly with his ambitious and inspirational attitude.
“Off the field, my partner Libby has been extremely supportive during my eight years at Hull KR and we now look forward to fostering relationships with her family and friends in the London area.”