The world number two, chasing the only grand slam title to elude him, next meets 18th-seeded Latvian Ernests Gulbis.
Raonic went close against Djokovic on clay in the Rome Masters semi-finals last month, losing 6-7 (5) 7-6 (4) 6-3, but this time the Serb played better.
"It's never smooth against Milos or any server of his calibre," Djokovic told reporters. "It was important to get the first set under my belt. Even though it was a straight-sets win, only a few points here and there decided the winner.
"Against such a player you have to wait for your opportunities and when they're presented to you, you'd better take them."
A couple of double faults in the 11th game put Raonic under pressure and Djokovic took full advantage, grabbing the opening set after unsettling his opponent with a dipping backhand.
The Serb, who now has a 3-0 record against Raonic, then took the second-set tiebreak when his rival missed a backhand.
The Canadian trailed 4-0 in the third set before retrieving one of the two breaks of serve.
Djokovic, however, ended the contest on his first match point when Raonic, the first Canadian male to reach the last eight of a grand slam in the professional era, sent a forehand wide.
"It is complicated to play against him because he has a great serve, powerful and accurate, difficult to anticipate," said Djokovic. "It was important to be mentally strong and consistent."
Raonic said there was a subtle difference between their meetings in Rome and Paris.
"I think where he stood out today compared to Rome was he was playing a lot closer to the baseline, he was not letting me dictate as much," the Canadian explained.
The world number two, who has only reached the final here once before when he lost to eight-times champion Rafa Nadal in 2012, dropped his serve just once, in the final set when victory was virtually assured.
Gulbis followed up his surprise win over Roger Federer in the last 16 by knocking out sixth-seeded Czech Tomas Berdych in straight sets on Tuesday.
"He is a very good player and to beat Roger and Berdych is impressive," said Djokovic. "He has been playing his best tennis, it will be difficult for me."
(Editing by Tony Jimenez)
Share
