The 26-year-old Portuguese striker has joined Traktorsazi for an undisclosed fee.
Paixao joined for Scottish Premier League side Hamilton Academical in 2009. He made his league debut for Hamilton on 15 August 2009 against Kilmarnock. Paixao appeared in 56 official games for Hamilton, scoring 10 goals.
Paixao is Traktorsazi’s fourth foreign players. The Tabriz-based team has already signed German Shpejtim Arifi as well as Brazilians Rodrigo Tosi and Robson Chavez Santana.
Traktorsazi will host Saba in fist week of the Iran Professional League on Tuesday.