Alves has regularly defended his Brazilian teammate in the Spanish press as the former AC Milan star has struggled in Madrid.
Asked who he would like to see Barca sign, Alves told the Guardian: "Kaka. Not just because he's my friend but also because I think he'd suit us very well. I really like the players we have got, who are phenomenal, but he would add a little bit to us. Off the pitch, he is very bright. He speaks five languages and has studied."