The 27-year-old has signed a four-year contract at Selhurst Park and becomes new head coach Pierre Sage's first acquisition of the summer transfer window.
A graduate of Barcelona's famed La Masia academy, Mingueza made 66 first-team appearances for the Catalan giants after making his senior debut in 2020.
He moved to Celta Vigo in 2022 and went on to score seven goals and provide 15 assists in 147 appearances for the club.
The versatile defender described joining Palace as an honour and expressed excitement about the new challenge.
Mingueza has earned four caps for Spain but missed out on this summer's World Cup squad.