"I really enjoyed my time with Dewsbury last season. There's a good atmosphere about the club and they've got a very talented coach."
Bolger is keen to get more game time with the West Yorkshire club after seeing his first team opportunities limited to just one Stobart Super League appearance so far this term.
"It's about getting more minutes on the pitch. The Championship is a very competitive and physical league and I'm hoping my spell with the club will make it easier for me to make the step up to Super League."
London Broncos will take on Dewsbury Rams in the Challenge Cup on April 15 at 2.00pm at The Stoop.