The Ipswich manager's Leeds counterpart Simon Grayson is delighted with the deal after making Bruce his seventh signing since clinching promotion from League One.
"Alex is going to be a good member of the squad. He can play at centre-back, right-back, and as a holding midfielder," Grayson told the club's official website.
"We felt we were short in those areas at this moment and we're delighted he's come. He's got a lot of experience, he's played in the Championship and the Premiership and he's what we want - a player who knows the division, is hungry and wants to be successful.
"We tried to sign him a year ago when we were in League One. Ipswich wouldn't let him go then we got a call a week ago to say he was available, and everything got agreed."