The France international, 27, denied all charges against him at Chester Crown Court on Monday.
They include seven counts of rape and further allegations of sexual assault and attempted rape between October 2018 and August 2021.
He will face trial on July 25 alongside co-defendant Louis Saha Matturie, who entered not guilty pleas to 12 charges, with both men currently on bail.
Matturie, 40, is facing eight counts of rape and four counts of sexual assault, relating to eight women between July 2012 and August 2021.
Mendy has been suspended by City amid the accusations.
The left-back has made 50 Premier League appearances since joining from Monaco in 2017, winning three top-flight titles.
He also has ten caps for France and a World Cup winners' medal from 2018.