Dier, who grew up in Portugal and played for Lisbon club Sporting until joining Tottenham in 2014, has impressed for his club this season in a holding role.
"We are more blessed with forward looking, attacking players, so this is a good opportunity for someone with a more defensive bent," manager Roy Hodgson told a news conference.
"We haven't got many of those players available to us. He deserves his chance because he's been a key figure for Tottenham at the start of their campaign."
He joins fellow Tottenham youngster Dele Alli in the 23-man squad for the matches against European champions Spain in Alicante and France at Wembley next week.
Manchester City midfielder Fabian Delph and Everton defender John Stones return to the squad after injuries.
While Dier has been given a chance to impress, Hodgson appeared to suggest the door was now closed on new faces to make a late bid for next year's finals in France.
"It is a great opportunity to look at players that have been with us but have not had much game time," he said.
"There will be no newcomers, no players out of left field."
Leicester City's Jamie Vardy, who has scored in eight successive Premier League games and is the top scorer in the top flight, will have a chance to bolster his bid for a Euro 2016 spot. He joins Wayne Rooney and Harry Kane as England's other strike options for the testing friendlies.
"Jamie has only played a handful of games for England, he should be happy to be in the squad and even happier if he makes the team," Hodgson said in response to Leicester manager Claudio Ranieri's opinion that Vardy should be played as a central striker, rather than out wide.
"He has a job to convince us he has the ability to play as a centre forward and not get too hung up about where he plays."
England are begining their build-up for the Euro 2016 finals having qualified with a 100 percent record.
Squad: Goalkeepers: Jack Butland (Stoke City), Joe Hart (Manchester City), Tom Heaton (Burnley)
Defenders: Ryan Bertrand (Southampton), Gary Cahill (Chelsea), Nathaniel Clyne (Liverpool), Kieran Gibbs (Arsenal), Phil Jones (Manchester United), Chris Smalling (Manchester United), John Stones (Everton), Kyle Walker (Tottenham Hotspur)
Midfielders: Dele Alli (Tottenham Hotspur), Eric Dier (Tottenham Hotspur), Ross Barkley (Everton), Michael Carrick (Manchester United), Fabian Delph (Manchester City), Adam Lallana (Liverpool), James Milner (Liverpool), Jonjo Shelvey(Swansea City), Raheem Sterling (Manchester City)
Forwards: Harry Kane (Tottenham Hotspur), Wayne Rooney (Manchester United), Jamie Vardy (Leicester City)
(Reporting by Martyn Herman, editing by Alan Baldwin)
