Onions joins Tim Bresnan and Steven Finn in a battle to decide the final place in the XI to start England's Ashes defence.
The trio played in England's warmup match against Essex for which James Anderson and Stuart Broad were rested.
Joe Root will open the batting with captain Alastair Cook in place of Nick Compton who opened in the home and away series against New Zealand.
"This is an incredibly exciting period of cricket coming up against Australia and we know we will need to play to our full potential throughout the entire Ashes Series if we are to retain the Ashes," national selector Geoff Miller said in a statement on Saturday.
"We are satisfied with our preparations so far ahead of the first test with both Graeme Swann and Stuart Broad recovering well from the injuries they picked up earlier this week."
England squad for 1st Test: Alastair Cook (captain), Joe Root, Jonathan Trott, Kevin Pietersen, Ian Bell, Jonny Bairstow, Matt Prior, Tim Bresnan, Stuart Broad, Graeme Swann, Steven Finn, James Anderson, Graham Onions.
Ashes Test series schedule:
Date | Match | Venue | Time |
July 10-14 | First Test | Nottingham | 1530 IST |
July 18-22 | Second Test | Lord's | 1530 IST |
Aug 1-5 | Third Test | Manchester | 1530 IST |
Aug 9-13 | Fourth Test | Chester-le-Street | 1530 IST |
Aug 21-25 | Fifth Test | Oval | 1530 IST |
Image: Graham Onions
Photograph: Tony Marshall/Getty Images
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