The study was aimed to produce potential coalfield map using geographic information systems (GIS) in the Milas-Yatagan Basin. Frequency ratio model was used to define the relationships between the coal occurrences and the selected variables which are significant for coal prospection. Formation, geologic age, lithology, rock types, depositional environment, distance to fault and slope data of the study area were used as variables. Frequency ratio values of the variables were calculated and assigned to variable's class attributes. All variable maps were summed according to the frequency ratio values of superposed pixels to calculate the probability index. The probability index values of the potential map were classified into five classes as very high, high, medium, low and very low probability areas. Finally, the potential map was compared with known coalfields in the Milas-Yatagan Basin and calculated distribution of the known coalfields on the probable areas. (C) 2012 Elsevier B.V. All rights reserved.