At 39, Nani has moved with his future in mind, with the deal including an expanded role with the club's development project.
Aktobe will be the 12th club of his career.
In a statement, the winger said of his move: "I am very excited about this new project and about the opportunity to help develop footballat the club and in Kazakhstan.
"FC Aktobe offers excellent conditions and I was very warmlywelcomed. I feel that together we can work to elevate the club not only domestically but also internationally."
Aktobe are five-time Kazakh League champions, and are chasing their first participation in a UEFA competition.
Since his last game with Estrela in 2024, Nani has completed the UEFA A Elite Youth Licence course, one of the highest coaching qualifications in Europe