The 18 year old said that he is “shocked” to be called up.
The youngster was brought into the squad on Monday ahead of Englands Euro 2020 qualifying games against Czech Republic and Montenegro.
He is yet to start a premier league game this season, however has played 19 times and scored 5 times.
After having his first call up to the U21s just last week he was shocked when he was told by U21 manager Aidy Boothroyd, that he was being promoted to the senior team.
“It’s been a crazy experience but I’m delighted,” Hudson-Odoi said. “I thought the manager was joking.
“I was shocked and then when I heard that I actually had to go over, I couldn’t believe it,” Hudson-Odoi added.
“I was delighted. It’s a dream come true. Now I’ve got to work hard, enjoy every moment and keep working to just hopefully make an impact when I get the opportunity.”
Hudson-Odoi was called up after full-back Luke Shaw joined John Stones, Fabian Delph and Ruben Loftus-Cheek in withdrawing from the squad.
England play Czech Republic at Wembley on Friday 22nd of March and then away to Montenegro on monday 25th of March.
Southgate again believing in the younger players.
Hudson-Odoi has only made 23 first-team appearances in his career and would become England’s eighth youngest player if he makes his debut against either the Czech Republic or Montenegro.
Theo Walcott is England’s youngest international. He was aged 17 years and 75 days when he made his debut against Hungary in 2006, having not played in the top flight.
Eleven of Hudson-Odoi’s 19 appearances for Chelsea this season have come as a substitute with his starts all coming in cup competitions.
Goalkeepers: Jack Butland (Stoke City), Tom Heaton (Burnley), Jordan Pickford (Everton)
Defenders: Trent Alexander-Arnold (Liverpool), Ben Chilwell (Leicester City), Michael Keane (Everton), Harry Maguire (Leicester City), Danny Rose (Tottenham Hotspur), James Tarkowski (Burnley), Kieran Trippier (Tottenham Hotspur), Kyle Walker (Manchester City)
Midfielders: Ross Barkley (Chelsea), Dele Alli (Tottenham Hotspur), Eric Dier (Tottenham Hotspur), Jordan Henderson (Liverpool), Declan Rice (West Ham), James Ward-Prowse (Southampton), Callum Hudson-Odoi (Chelsea)
Forwards: Harry Kane (Tottenham Hotspur), Marcus Rashford (Manchester United), Jadon Sancho (Borussia Dortmund), Raheem Sterling (Manchester City), Callum Wilson (Bournemouth)