Lucas Paqueta was on target for the holders just minutes after coming on as La Roja upped the ante after Gabriel Jesus was sent off.
In the first-half it was all Seleccao who created the better chances, but couldn't find a way past Claudio Bravo as Roberto Firmino, Danilo and Gabriel Jesus were all guilty of missing crucial opportunities.
Martin Lasarte's side looked dangerous going forward without ever testing Alisson. But they found themselves behind early in the second-half when Paqueta, who'd only been on the field for less than a minute, intercepted a poor clearance at the back and coolly slotted home the opener.
Brazil were in front but just two minutes later Gabriel Jesus was sent off for a nasty challenge on Eugenio Mena, giving Chile a numerical advantage which they used to pile on the pressure on the holders.
However, they couldn't find the back of the net, and Paqueta's goal got the job done. Brazil face Peru in the semi-finals on Monday. Here are the hits and flops from the match:
Hit: Neymar (Brazil)
The match-winner may have been Lucas Paqueta but Brazil's real inspiration behind the victory was Neymar. The PSG ace was in top form again and helped create the goal for Paqueta with some fine work on the ball, strengthening his case for the Copa America 'player of the tournament' prize.
With two goals and assists each in three games, Neymar came back into the starting XI after sitting out the Ecuador draw. He conjured up the highest number of chances with three, while Chile had no answer to his precocious dribbling skills besides just hacking the player down.
Flop: Charles Aranguiz (Chile)
It might have been easier to pick out Chile's attacking duo, Alexis Sanchez and Eduardo Vargas, for their inability to find the net. While both were dangerous and asked questions of Brazil's defense, Charles Aranguiz was a real disappointment.
He attempted just two crosses in the match, both of which failed to beat Marquinhos, and lost possession 10 times. While his passing range was impressive, nothing meaningful came of it.
Make no mistake, Aranguiz is a quality player, and has been a beacon of consistency for his side, even in this edition of Copa America so far, but Brazil's tight defense did a good job of negating his influence.