Gento played for Real Madrid for 18 seasons and made 600 appearances for Los Blancos.
Gento is the only player to win six European Cups -all with Real Madrid- while he added 12 La Liga titles and two Copa del Reys.
He won 43 caps for Spain and played at two FIFA World Cups.
In a statement the club said: "Real Madrid C.F., the club's president and the board of directors are deeply saddened by the death of Francisco Gento, honorary president of Real Madrid and one of the greatest legends of our club and of world football.
"Real Madrid would like to express its condolences and send its love and sympathy to his wife Mari Luz, to his sons Francisco and Julio, to his granddaughters Aitana and Candela and to all his relatives, teammates and loved ones.
"Paco Gento is the only player in the history of football to have won the European Cup 6 times. He represented our club between 1953 and 1971, and in his 18 seasons at Real Madrid he won not only the six European Cups, but also 12 Leagues, two Spanish Cups, one Intercontinental Cup, one Mini World Cup and two Latin Cups. He played 600 games for Real Madrid, scoring 182 goals. Gento was also capped 43 times by the Spanish national team.
"Paco Gento truly represents all the values of Real Madrid, and has been and will continue to be a reference for madridistas and for the sporting world. He will always be remembered by madridistas and all football fans as one of their greatest.
"Francisco Gento passed away at the age of 88. Real Madrid would also like to express its condolences to all Real Madrid members and fans."
