Sol Bamba becomes Neil Warnock's second signing.
The former Leeds and Leicester defender has over 40 caps for Ivory Coast and has also played in France, Scotland and Italy.
He has signed a contract unti the summer of 2018.
Bamba, speaking to Cardiff City Player HD said: “I’m excited to be here. I always want to work with the gaffer, so as soon as this chance arose I jumped at it.
“I know the league very well and am looking forward to offering my experience and leadership to Cardiff City.”
First Team Manager Neil Warnock added: “I tried to sign Sol a few years ago when he was at Leicester, on a couple of occasions. They didn’t come off then, but now is the right time and opportunity to bring him in.
“Sol’s a leader and he’s another good addition for us.”
City are hoping to conclude a deal for striker Marouane Chamakh next and former Man Utd and Sunderland full back Kierann Richardson has also been linked.