The former Chelsea midfielder and coach led the Turkish club to their first trophy in a decade with a 2-0 win over Alanyaspor on Wednesday – while in charge on an interim basis.
The 48-year-old left the Stamford Bridge coaching staff to become assistant at the Turkish club in February and last month took caretaker charge following the departure of Huseyin Cimsir.
He spent eight years as a Chelsea coach and was twice assistant manager.
It is a first management role for Newton, who had stints as an assistant at Chelsea to Robert Di Matteo when they won the Champions League and FA Cup in 2012, and Guus Hiddink. Newton has said he felt there was “more opportunity” as a black manager in Turkey than in his homeland.