Abstract: Using systematically historical and modern comparative methods, it has been discussed that oil source rock maturity, lithological properties and oilfield conditions of worldwide oilfield generated from coal and coal bearing formations.The study results indicated that the coal may generate oil, but difficult to form commercial oilfields;the mudstones in coal bearing formation are main component contributed to form oilfield generated from coals, as well as it is difficult to form oilfield generated from low rank coals.