Taylor, 33, who has penned a one-year contract, travelled to Italy with the first-team squad on Monday for pre-season training.
Head coach David Hockaday told the club's official website: "I'm absolutely delighted to get Stuart Taylor here. He comes highly recommended by everybody. He has lots of experience and is a great professional.
"He will be perfect for our dressing room because we have a very young team. I'd like to give Stuart a big welcome to Leeds United."
Taylor began his career at Arsenal before moving on to Aston Villa in 2005 and had a spell at Manchester City from the summer of 2009 to August 2012.
He failed to make a first-team appearance last season at Reading, where his contract expired earlier this month.