England bench Burgess
Joseph takes over from Brad Barritt, who moves back to inside centre for Burgess, with the Bath Rugby player on the replacements bench.
Ben Morgan replaces the injured Billy Vunipola at No.8.
Joe Launchbury comes in for the injured Courtney Lawes for his first World Cup start and Nick Easter is included on the bench for his third tournament following his call-up for the injured Vunipola to provide specialist No.8 cover. George Kruis gets his first World Cup matchday experience in the 23.
England head coach Stuart Lancaster said: "Jonathan Joseph and Ben Youngs are both fit and raring to go, as are the rest of the squad for what will be a huge game against a very good team. England-Australia matches at Twickenham are always massive occasions, this one more than ever, and we want everyone behind us so we can get the result we all want."
England: 15 Mike Brown, 14 Anthony Watson, 13 Jonathan Joseph, 12 Brad Barritt, 11 Jonny May, 10 Owen Farrell, 9 Ben Youngs, 8 Ben Morgan, 7 Chris Robshaw, 6 Tom Wood, 5 Geoff Parling, 4 Joe Launchbury, 3 Dan Cole, 2 Tom Youngs, 1 Joe Marler.
Replacements: 16 Rob Webber, 17 Mako Vunipola, 18 Kieran Brookes, 19 George Kruis, 20 Nick Easter, 21 Richard Wigglesworth, 22 George Ford, 23 Sam Burgess.
Date: Saturday, October 3
Venue: Twickenham, London
Kick-off: 20.00 (19.00 GMT; 6:00 AEST Sunday, October 4)
Referee: Romain Poite (France)
Assistant referees: George Clancy (Ireland), Marius Mitrea (Italy)
TMO: Shaun Veldsman (South Africa)