Mallinder said: "Matt is a good leader who did a fantastic job for us last year. He's been in top form for his club and has the respect of all the players and management."
Among those making their debuts at U21 level are Bath hooker Chris Brooker, Tykes number 8 Jordan Crane and Gloucester backs Ryan Lamb and Anthony Allen, all from last year's Grand Slam winning England U19 squad.
"It's great to have such good youngsters coming up to join us," said Mallinder. "Even though they're still young they have a lot of premiership experience between them which will undoubtedly help them adapt to the next level of international rugby."
The match, against U21 Grand Slam champions Wales, kicks off at Worcester's Sixways at 8pm on Friday 3 February and will be televised live on Sky Sports.
ENGLAND U21 team: Olly Morgan - Gloucester; James Hoyle - Newcastle Falcons, Matt Cornwell - Leicester Tigers (captain), Anthony Allen - Gloucester RFC, Mike Brown - NEC Harlequins; Ryan Lamb - Gloucester RFC; Ben Foden - Sale Sharks Dylan Hartley - Northampton Saints, Chris Brooker - Bath Rugby, David Wilson - Newcastle Falcons, Richard Blaze - Worcester Warriors, Tom Croft - Leicester Tigers, Chris Robshaw - NEC Harlequins, Michael Hills - Sale Sharks, Jordan Crane - Leeds Tykes: Reps: Neil Briggs - Sale Sharks, Mark Lambert - NEC Harlequins, Tom Ryder - Saracens, James Haskell - London Wasps, Nick Runciman - Worcester, Shane Geraghty - London Irish
22 Topsy Ojo - London Irish