Bernard has signed a pre-contract agreement with Arsenal and joins as a first-year scholar, with professional terms to follow once he turns 17 next year.
The move comes after his contract situation at Crystal Palace lapsed, with Arsenal required only to pay a training compensation fee rather than negotiate a transfer with their London rivals.
The striker scored more than 40 goals for Palace's academy sides last season, form that also earned him a step up to the club's Under-18s despite his age, where he netted six times in the Under-18 Premier League from just 708 minutes on the pitch. His performances have also been recognised at international level, with four goals in eight appearances for England's Under-16s.
Bernard becomes one of several academy recruits at Arsenal this summer, joining Elijah Upson from Tottenham Hotspur and Axel Donczew from Cardiff City among a wider intake that has also included Igor Tyjon from Blackburn Rovers, James Scanlon and Habeeb Ogunneye from Manchester United, and goalkeeper Phoenix Blayney on a pre-contract from Larne, as the Gunners continue to target the best emerging talent from academies across the country and beyond.
Bernard marked his exit from Selhurst Park with a heartfelt message on Instagram, reflecting on eight years at the club.
"After eight unforgettable years at Crystal Palace, I have decided to say goodbye," he wrote. "I have grown up playing for Crystal Palace and it has provided so many wonderful moments in blue and red.
"Crystal Palace has shaped me as a person and a player, becoming a crucial part of my life. It has always been a pleasure playing at the club over the last few years and this part of my journey will always have a place with me.
"Thank you to all my coaches and teammates that have pushed me to become a better player and have helped me in my journey at the club. I will forever be grateful for the past eight years I've had with this club."