Posting today on the @5LiveF1 Twitter account, the station tweeted: "So the news is out! @AlguersuariJA is joining the 5 Live F1 team for 2012!! Great news!!"
Alguersuari became the youngest Formula One driver in history to start a Grand Prix when he turned out for the Toro Rosso team at the Hungarian Grand Prix in 2009.
After being dropped by Toro Rosso just before Christmas, Alguersuari will start his sports broadcasting career at Radio 5 Live.
He will provide "expert analysis" for the 5 Live F1 team, which has been rebuilt by the BBC after lead commentator David Croft and former pit lane correspondent Natalie Pinkham moved to Sky for the launch of the new Sky Sports F1 channel.
> Sky mines BBC talent for Formula One presentation team
Alguersuari will follow the entire season for 5 live, complementing the commentary team of lead commentator James Allen and new pit lane reporter Jennie Gow.
He has some previous radio experience, hosting a music show on Ibiza Global Radio and regularly DJing in Spain under the stage name Squire. He also released his debut album, Organic Life, in September last year.
"It's great to be part of the BBC's F1 commentary team on Radio 5 live," said Alguersuari.
"It will be interesting to look at the action from a different angle and bring that excitement and insight to listeners.
"Given that I'm still only 21, this agreement permits me to return to F1. It promises to be another exciting season and I can't wait for it to start."
BBC Radio 5 live controller Adrian van Klaveren added: "We're delighted to have Jaime on board, his engaging personality makes him a great addition to 5 live for the 2012 F1 season.
"We are going to make the most of Jaime's first-hand experience right now knowing he could well be driving for one of the teams again in the near future."
The BBC said that Alguersuari's appointment completes its F1 team for 2012. Jake Humphrey will again lead coverage on television, with Eddie Jordan as primary analyst and David Coulthard combining the role of analyst and co-commentator. Ben Edwards joins as lead commentator, while Gary Anderson and Lee McKenzie will provide analysis.
The new F1 season gets under way on March 18 with the Australian Grand Prix. The BBC has rights to show just half of the season's races live on TV under its controversial joint deal with pay-TV broadcaster Sky.
> BBC announces Formula One coverage plans for 2012