The 20-time Grand Slam winner claimed a record eighth trophy at the Aviation Club.
The Swiss second seed was untouchable throughout much of the 69-minute final as he gained revenge for his fourth-round Australian Open defeat by the 11th-ranked Greek youngster.
“It’s so special to win my eighth here combined with 100,” Federer said. “I had tough opponents all the way through – right up to Stefanos today.
“He’s already having a great career, the game is in good hands.”
Federer joins Jimmy Connors (109) as the only other man to have won 100 titles.
His 99th trophy came last October at his home event in Basel.
He missed out on his century at the Paris Masters, the ATP Finals and the Australian Open.
Federer had to work hard this week, winning in three sets over Philipp Kohlschreiber and Fernando Verdasco.
Tsitsipas saw the end of an eight-match winning streak as he arrived in the Gulf with the Marseille title from last weekend.
Federer broke in the opening game of the final, but had to battle to claim the opening set.
Tsitsipas saved three set points in the final game before Federer – who faced two break points – finished off the set as Tsitsipas returned wide.
On his first visit to #DDFTennis, Roger Federer was accused of tanking and the tournament wanted to withhold his prize money. 17 years later in Dubai, Federer captures his 100th career title.
“I was young and crazy. Sometimes you have to learn it the hard way,” he says. pic.twitter.com/kN88v7bhUl
— Sport360° (@Sport360) March 2, 2019
In the second, a break in the penultimate game for 5-4 and a service hold a game later were enough as Tsitsipas put a forehand into the net.
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