Both actors are surprising choices for the role, with Ben Affleck last donning Batman's suit in 2017's Justice League.
Actors Armie Hammer and Aaron Taylor-Johnson were also considered for the role, according to The Hollywood Reporter.
At 32, Pattinson would also be the youngest actor to ever play the DC Comics superhero.
Affleck had been expected to star and direct the next Batman movie but told Jimmy Kimmel Live in February he couldn't make it work.
"I tried to direct a version of it and worked with a really good screenwriter but just couldn't come up with a version, I couldn't crack it," Affleck told Kimmel.
"So I thought it was time to let someone else take a shot at it. They got some really good people, so I'm excited."
Before Affleck, Batman was played by Christian Bale in the Christopher Nolan-directed Dark Knight trilogy that was a hit with critics and audiences alike.
Pattinson playing Batman is a surprising choice for the English actor who has shunned mainstream movie roles in recent years.
Reports Pattinson was in the running to play Batman drew a mixed reaction on Twitter, with some complaining the former teen-heart throb was woefully miscast.
Since The Twilight Saga: Breaking Dawn — Part 2 came out in 2012, both he and co-star Kristen Stewart have favoured more indie fare.
Pattinson's latest film is the Claire Denis-directed High Life, which will screen at the Sydney Film Festival next month.
