Black yeast fungi play critical role in degradation of petroleum polluted soils. Little attention has been paid to the biodiversity of black yeast fungi in Iran. In this paper, diversity of black yeast fungi was studied in petroleum polluted soils in Tabriz and Urmia regions. Soil samples were collected from petroleum polluted areas in vicinity of oil storage tanks in Tabriz and Urmia cities (East and West Azarbaijan provinces) in summer 2009. Isolation was carried out by using "floatation in mineral oil" method with minor modifications on Mycosel medium. In total, 38 isolates with melanized colonies were recovered and then purified using repeated streaking method.