Koepka, who won the US Open for the second straight year at Shinnecock Hills in June, has now won three of the last six Major Championships. This will be Koepka's first appearance in the competition since 2015, when he finished runner-up to Thorbjørn Olesen.
He will be joined by fellow American and World Number 15 Tony Finau, who this year finished tied tenth in The Masters, fifth in the US Open and ninth in The Open at Carnoustie.
Both are members of the US Ryder Cup team which takes on Europe in France the week before the Alfred Dunhill Links.
Koepka said, "I’m so delighted to be coming back to the Alfred Dunhill Links, and of course to play once again at St Andrews. Last time I played in the Dunhill it was with my dad Bob, and it was a few days I will never forget.
"Being able to do that at the Home of Golf in such a prestigious competition with the great Scottish galleries was a unique moment for both of us.”
I’m so delighted to be coming back to the Alfred Dunhill Links, and of course to play once again at St Andrews. Last time I played in the Dunhill it was with my dad Bob, and it was a few… https://t.co/IjfaqfAZDQ— Brooks Koepka (@BKoepka) September 13, 2018
Koepka will be renewing competition with England’s Tommy Fleetwood, who finished second to him at Shinnecock, after his final round 63 equalled the lowest round in US Open history.
Tyrrell Hatton is aiming to become the first man to win the Alfred Dunhill Links trophy three straight times. Like Fleetwood, Hatton will arrive in Scotland following his Ryder Cup debut at Le Golf National.
Also among the entries for the Championship, which takes place from October 4-7, are Major Champions Martin Kaymer, Ernie Els, Padraig Harrington, Louis Oosthuizen and Graeme McDowell, plus Spain’s Miguel Ángel Jiménez, winner of the Senior British Open in July.