Both players were part of the England Under-20s squad last season and have previously represented the Three Lions at U16, U17 and U19 level before that.
And the midfield duo will now have an opportunity to develop further at domestic level after agreeing to sign on a six-month loan with the League One club until 3 January 2016.
Joe Rothwell, pictured here in action for England U17s, has signed on loan for Barnsley
For Pearson, it’s a familiar pathway after he spent a similar spell at Oakwell last season and made 22 appearances for the Tykes whilst Rothwell gained Championship experience on loan with Blackpool.
"Ben really impressed me last season - both when he played against and for me," revealed Barnsley head coach Lee Johnson.
"He is a tremendous talent with energy to burn and is a good passer of the ball. He will be an asset in our midfield and I’m really looking forward to working with him again.
"I'm really excited to have Joe on board, as well as Ben.
"We are very lucky to have two highly-rated midfielders on our hands and I’m really grateful to Manchester United for allowing us to bring them both here."
Speaking to BarnsleyFC.co.uk, Pearson added: "I'm really pleased to be back, I had a great time here last season - making my professional debut - and want to pick up where I left off but help take us that one step further."
And Rothwell said: "I'm really excited to be here, I’ve heard a lot about the place from Ben Pearson. He couldn't speak highly enough of his time here and I just can't wait to get going.
"I had no hesitations about coming here after speaking with Lee Johnson. The club almost made the play-offs with Ben here last season so, hopefully, we can go one better this time."
Both players are now eligible to play for Gareth Southgate’s England U21s in the forthcoming Euro campaign, so will be aiming to catch both his, and United boss Louis van Gaal’s eye with their performances at Oakwell.
