Ali Yousif, 27, started his playing career in Al-Quwa Al-Jawiya in 2014 and has also played in Naft Al-Wasat, Baghdad FC and Al-Shorta.
He has most recently played at Al-Zawraa.
Yousif is the third Iraqi player to join Sanat Naft.
Iraqi goalkeeper Fahad Talib and defender Abbas Qasim have previously joined the Iranian football club.