Within 6 minutes of the start Swindon had gone 2-0 down with both opening goals being scored from Craig Mackail-Smith after some poor Swindon defending.
By 22 minutes Lee Frecklington had made it 3-0 after a Swindon failed to clear the ball away once more.
2 minutes later Swindon had pulled a goal back from close range from David Ball.
Matt Richie, on loan from Portsmouth, then made it 3-2 on the half hour mark with a powerful 25 yard shot which the Posh 'keeper could only slow down, but couldn't prevent from going into the net, even though from the away end it looked like he had tipped it over the bar.
Then just before half time David Ball made it 3-3 with a close range goal.
Phil Smith came on to replace David Lucas in the Swindon goal at the start of the second half.
Boyd made it 4-3 on 58 minutes after some more poor Swindon defending, then on 78 minutes a Peterborough hand ball in the box resulted in a Swindon penalty which Charlie Austin took and scored to make it 4-4.
That's the way the game looked to be ending, until a late Kevin Amankwaah own goal deep into stoppage time made it 5-4 to the home side.
This is the most goals seen at a Swindon match for over 17 years since Swindon beat Birmingham City 6-4 in 1993.