The Selecao boss insists the 34-year-old veteran will be one of three keepers named for the tournament in his native country, despite his lack of playing time for QPR.
The former Inter shot-stopper has yet to play for Queens Park Rangers yet this season after failing to secure a move away from the club over the summer, prompting speculation that his place with the Selecao could be in jeopardy.
Scolari has assured otherwise, though. Speaking to reporters ahead of Wednesday's friendly with Portugal, Scolari said he has reserved a place for the 34-year-old Cesar, whom he still regards as one of the world's best.
"I am going to give you an exclusive - even if he is not playing for his club, he will be there," Scolari said. "Among the three places reserved for goalkeepers, there will be one for him.
"We have a lot of training sessions and friendly matches before the World Cup, but even if he doesn't play for his club, he will be ready.
"For me, he is still among the best in the world and will stay with us."