Harrington was a vice captain under Thomas Bjorn when Europe won the Ryder Cup in September
Padraig Harrington will be captain Europe if they defend the Ryder Cup on American soil by 2020.
The Irishman, 47, was a vice captain when Europe won the trophy in September under the leadership of Thomas Bjorn in France.
Harrington played in six consecutive Ryder Cups from 1999 and was four times a member of the winning team
Players including Rory McIlroy and Justin Rose supported Harrington to lead Europe in Whistling Straits, Wisconsin.
Harrington, a threefold big champion winner, has experience with the PGA championships course.
The likes of former world number Luke Donald and Lee Westwood were mentioned as potential captains, although Westwood – who was also vice captain of Bjorn – has indicated a preference to take on the role during the 2022 event in Rome
Harrington, who is currently recovering from a broken wrist, becomes the second man from the Republic of Ireland to become the captain, following Paul McGinley in 2014.
After winning the trophy under McGinley, Europe well beaten 17-11 under the captain of Darren Clarke from Northern Ireland, the last time it was challenged in 2016 in the US.
But a resounding success of 17½-10½ under Bjorn achieved a seventh success for Europe in the last nine Ryder Cup events.
The US has yet to give their next captain a name, with 1992 Masters champion Fred Couples and Steve Stricker – who was born in Wisconsin – among the leading candidates.
BBC golf correspondent Iain Carter
Winning a victory in the Ryder Cup is one of the most difficult tasks of golf. As Europe has proven at Le Golf National and the US at Hazeltine, home benefits can make a huge difference.
It is therefore logical that the continent turns to such a resourceful, committed and intelligent figure as Harrington. There was no one better qualified to lead Europe in his defense by 2020.
The thrice big winner recommends enormous respect among his colleagues. He is a popular figure among American golf enthusiasts, has played all three PGA championships in Whistling Straits and has served as vice captain in the last three Ryder Cups, the ideal choice to succeed Thomas Bjorn.