The 27-year-old centre and winger will join the club on a one-year deal after finishing the 2014 season with the South Sydney Rabbitohs.
"Beau is a great competitor and athlete, and will be a valuable addition to our side for 2015," Eels Head Coach Brad Arthur said.
"He will bring back line experience to our team, and maturity to our young squad."
"It's a fantastic opportunity to come to a club that I believe is on the rise, with a lot of young talent," Champion said.
"I'm looking forward to the chance to play alongside these young players and be part of the Eels next year."
Champion has represented City Origin and the Indigenous All-Stars in 2010-11, and has played more than 100 NRL games.
"It's a great sign for the Eels to have players of Beau's calibre interested in joining our ranks," Parramatta Eels CEO Scott Seward said.
"The club is building a squad with depth and balance in key positions, and I look forward to seeing what Beau will bring next season."Like