The club have described the agreement as an improved deal for the versatile 21-year-old, who joined from Leeds in July 2009 during Martin O'Neill's time in charge.
'I am absolutely delighted,' he told Villa's website. 'The club has shown great commitment in me by offering me this deal and I was more than happy to sign it.'
Deal me in: Delph (left) is happy after signing his new Aston Villa contract
Delph added: 'I am happy and my family are happy - so everyone is happy. I want to push on now, improve and play a part as we look to finish the season on a high and build for next season.
'I am really pleased to have extended my association with the club.'
Villa boss Gerard Houllier hailed Delph's attitude.
'I know Fabian hasn't played a lot for us because he has just got over his long-term injury but we are very confident he will become a very good player for Aston Villa,' he said.
'The fact he signed the contract means he trusts us too. I think he's a good footballer, he will get stronger and stronger and he will improve his game.
'When you sign a player - or re-sign a player - you need to make sure he has the right attitude for the club and the fans and Fabian certainly fits that bill.'
England Under 21 international Delph has suffered a largely frustrating season after an anterior cruciate ligament injury suffered at the end of the 2009-10 campaign.
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Source: Daily Mail
Source: Daily Mail