Following a head on collision during the A League game against Saracens Storm earlier this year, the 33-year-old has failed to recover and after seeking professional specialist advice since, he has been advised to retire from the sport.
A rarity in the modern game, Birkett has been a one club man for his entire career, having made his debut for Wasps against London Irish at Loftus road in 1999.
The second row was part of a team who won almost every accolade in the game, playing an integral part in the team that won the Premiership finals in 2003, 2004, 2005 and 2008 and also featuring in the victorious Heineken Cup final in 2004.
Birkett said: "After 14 years of rugby with London Wasps my body has unfortunately given up on me. However, I leave the game content in the fact that I was a part of an amazing era in Wasps history.
"Those memories will never leave me and I'm incredibly proud of what we achieved. I've made some fantastic friends along the way and I have enjoyed almost every minute.
"The timing of my departure from the game is disappointing for me as I will not be able to be part of the new era at Wasps, which I genuinely believe has enormous potential.
"It's been a pleasure working with such raw young talent and I'm sure that Dai (Young) and the rest of the coaching team will continue to create a team to be reckoned with.
"My thanks go out to all of the Wasps family who have made it such a great place to be over so many years and I am sure I will see you in the stands!"
Director of Rugby Young said: "Since I came to the club last season, Richard has been an integral part of the squad. As a senior player he has been a leader both on and off of the field.
"In the modern game it is very rare that a player will stay with a club for their whole career but Birky has been a key component of this club for a 14 year period and he will be a loss to us.
"He formed a tremendous partnership with Simon Shaw throughout a very successful period for the Club and although he didn't get the international recognition that others in that side did, he was a fundamental part of their success and will go down as a true Wasps great."
RPA Rugby Director, David Barnes, said: "Rich is one of the longest serving one club players in the Aviva Premiership and it must be a huge blow to Wasps to lose such an experienced player.
"It's also a great shame to be losing Rich from the RPA Players' Board as our incumbent Wasps' Rep as he's hugely respected by his peers and provides a voice of authority within the game.
"As with all of our RPA members we will continue to support Rich and his family through our Player Development Programme as he makes the transition from professional sport to a second career."