Broad, 37, is England's second-highest test-wicket taker with 602 victims in 167 matches, behind only his long-time team mate James Anderson (40) who has 690.
"Tomorrow - well Monday - will be my last game of cricket," Broad told Sky Sports.
"It's been a wonderful ride, a huge privilege to wear the Nottinghamshire and the England badge as much as I have and I'm loving cricket as much as I ever have."
Broad and Anderson will be key players when England bid to bowl Australia out in the final test at The Oval on Sunday. England, who lead by 377 runs, need victory to level the series.
"It's been such a wonderful series to be a part of and I've always wanted to finish it on top," Broad said. "This series feels like one of the most enjoyable and entertaining I've been a part of.
"I've got a love affair with Ashes cricket and I think I wanted my last bat and bowl to be in the Ashes."
Anderson is third on the all-time list of test wicket-takers behind Sri Lanka's Muttiah Muralitharan and Australian Shane Warne, both spinners, with Broad in fifth place.
Broad made his test debut in 2007 against Sri Lanka and has also played 121 one-day and 56 T20 internationals.
He has taken an England-record 151 test wickets against Australia, the highlight coming at Trent Bridge in 2015 when he recorded extraordinary figures of 8-15 to lead his side to victory.
