The signing to the Albury-based team comes off the back of a strong end to the Dunlop Super2 Series last year where he claimed pole position and won two races in Newcastle.
The 22-year-old currently lies fifth in the Super2 Series standings for Image Racing with a best finish of fourth.
Albury-born Boys said his Bathurst 1000 debut is a major milestone in his career.
“I'm honestly so pumped and I can't thank Brad (Jones) and Kim (Jones) enough for the opportunity,” Boys said.
“To race at the Bathurst 1000 has been a dream of mine since my first ever go kart race.
“BJR gave me my first ever laps in a Supercar three years ago and I've really enjoyed every chance I've had to work with the team so far and believe we'll be in for a strong chance.”
Boys drove with Brad Jones Racing at The Bend Motorsport Park earlier this year as part of the pre-season test.
Hazelwood, who drives the #14 Holden ZB Commodore, said he was looking forward to having Boys on board.
“I've known Jordan since karting and always rated his race craft and ability,” said Hazelwood.
“It's great to see that he's been able to show what he's capable of during the latter stages of 2019 with his first Super2 win.
“I have no doubt we'll be able to produce great results together at BJR.
“This is the third year in a row that I've worked with a rookie co-driver so I definitely feel like I have the tools and tricks up my sleeve to help him make the transition and manage the situation best.”
Boys' signing leaves two seats open at the Brad Jones Racing. Co-drivers have yet to be announced for Jack Smith and Macauley Jones.
Super2 Series leader Thomas Randle will join Nick Percat in the R&J Batteries entry at this year's Bathurst 1000, which will take place on October 15-18.