Eze moves to Selhurst Park on a five-year contract and becomes manager Roy Hodgson’s second summer signing after Nathan Ferguson.
Eze featured in all of QPR’s 46 Championship games last season, scoring 14 goals and providing eight assists.
The 22-year-old forward’s arrival will help augment a Palace forward line that scored the second least number of goals (31) after relegated Norwich City (26) last season.
Eze said: "As a football club, I feel like there are great players here and it's a brilliant opportunity for me to come and be with these players, to link up with them and to really push on."
Palace chairman Steve Parish added: "Eberechi is a player whose development we have followed closely.
"We are delighted he has chosen to sign for us over the other clubs that were interested and we feel that this is the right club for him to continue his development.
"With our academy recently securing category one status, this further illustrates our focus on youth as we look to consolidate and improve upon our position as a Premier League club."
Crystal Palace will host Southampton in their first Premier League game for the 2020/2021 season on September 12.
