Al-Ain, who are based in the United Arab Emirates, have moved to sign Bastos on a three-year deal following his four-year spell in France with Lille and Lyon.
Bastos had been on loan at Schalke 04 in Germany since January, but Schalke's general manager Horst Heldt has admitted that they had little say in the future of the left-sided player, although they were not interested in his signing on a permanent basis.
"Michel Bastos is leaving our club with immediate effect," Heldt told Westdeutsche Allgemeine Zeitung.
"We would have had to buy the player to keep him here, and we did not want to do that.
"With this decision made, we finally helped Michel Bastos to get his wish fulfilled."
Bastos has made 10 international appearances for Brazil, scoring once against Zimbabwe in 2010.