England captain Alastair Cook won the toss in overcast conditions that promised to assist swing and seam bowling and saw his decision vindicated in the most dramatic style imaginable, with paceman Broad taking two wickets in the first over of the match.
Broad, leading the attack in the absence of injured James Anderson -- England's all-time leading wicket-taker -- needed just three balls on his Nottinghamshire home ground to take his 300th Test wicket when opener Chris Rodgers, on nought, edged to Cook at first slip.
It was the first duck of Rogers's 46-innings career in Test cricket.
Four balls after becoming just the fifth England bowler after Anderson, Ian Botham, Bob Willis and the late Fred Trueman to take 300 Test wickets, Broad struck again.
Steven Smith, squared up and aiming legside, was held by Joe Root at third slip for six.
Durham quick Mark Wood, in for Anderson, then reduced Australia to 10 for three.
Wood struck just two balls into the second over when David Warner, Rogers' fellow left-handed opener, was caught behind by wicket-keeper Jos Buttler off the inside edge by a sharply moving delivery that cut back off the pitch.
Rogers and Wood became the first Australia openers to both fall for ducks in an Ashes Test innings since Arthur Morris and Jack Moroney at Brisbane in 1950.
Top-order batsman Shaun Marsh, brought in to replace dropped younger brother Mitchell, then fell for a duck when he was caught in the slips by Ian Bell off Broad.
And the 29-year-old Broad then had Adam Voges (one) brilliantly caught one-handed by diving fifth slip Ben Stokes to leave Australia 21 for five in the fifth over.
Australia captain Michael Clarke's desperate run of form continued when, driving loosely outside off stump against Broad, he was well caught by a leaping Cook at first slip to leave the tourists 29 for six.
The 34-year-old Clarke's exit meant one of the best batsmen of his generation had now managed just 104 runs in seven innings this series at an average of 17.
Broad, the son of Ashes-winning former England batsman Chris Broad, had taken five wickets for six runs in 19 balls.
It was the 14th time in 83 Tests that Broad had taken five wickets in an innings.