The 47-year-old will lead the visiting team as they defend their title against the United States at Whistling Straits in Wisconsin in September next year.
Bjorn's side put on a ruthless display while outplaying the United States in a 17.5-10.5 victory at Le Golf National in September a year ago.
Harrington has served as a vice captain in each of the last three Ryder Cups, and he became the front-runner for the job once Lee Westwood took his name out of consideration late a year ago.
Thomas Bjorn has given his backing to Padraig Harrington, who will succeed him as Europe's Ryder Cup captain for the tournament in 2020. "I've actually learned a lot more as vice-captain than you do as a player". "I don't think I ever thought I wasn't going to do it, but I wanted to make sure I was doing it for the right reasons".
So did he really want a job that will consume his life and effectively put his playing career on hold for the next two years? "But it's not something that I take on without a certain amount of trepidation". Cynics might suggest that captains choose their vice-captains simply based on who their friends are, but Harrington appears to appreciate the mix of characters required in the European team room.
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The update comes after he was convincingly outclassed in a practice session with world No 1 Novak Djokovic on Thursday in which the Serbian won 10 of 12 games.
Six of the last seven contests have been won by the home side and, as Harrington himself has pointed out, it took a "Miracle at Medinah" for the one away victory to occur.
"I'm putting it on the line - we know when you're a successful Ryder Cup captain it's great and a losing captain - it's his fault".
The Irishman played in six Ryder Cups (four wins) and was vice captain at the last three (Gleneagles, Hazeltine and Paris).
He has got great experience in the USA, so he won't be intimidated.
"And secondly the course is a European-style of course, it's windy and has a links-feel to it". He won't want to change a winning formula, he knows what works and - perhaps more importantly - what doesn't work, and he'll stick with that. Thankfully we are going to Whistling Straits which is just a strong golf course.
The U.S.is expected to name its 2020 captain sometime this spring.
"There seems to be a natural progression at the moment", Harrington said of the European Ryder Cup selection process for Captains.