The Spaniard has already driven for the team on Grand Prix weekends at Silverstone and Monza, on top of testing for them at three different venues so far this year.
"I'm very happy to be given another chance to drive the car this weekend in Brazil," said Juncadella, who will substitute for Sergio Perez in FP1 at Interlagos. "I feel confident after my outings in Silverstone and Italy and I look forward to continue gaining more experience with the team."
Juncadella, 23, also has previous experience of the Brazilian Grand Prix circuit, having race there in Formula BMW in 2008.
"The Brazilian track brings back good memories, as I achieved two podium finishes back in 2008," he added, "but I can't wait to go back and see what it's like to drive it in an F1 car!
"The fact that I know the track and that I'm not new to the team anymore will definitely be two positive elements that will allow me to focus on my driving and on doing the best job possible for the team straight away."