Abstract: In this paper, the thermal evolution and hydrocarbon generation history of source rocks in Bailian sub?sag of Fushan sag in Beibuwan basin are studied and recovered using BasinMod basin simulation software and EASY% Ro model, and the results show that the maximum value of hydrothermal flow in the rifting stage of the Early Eocene reached 68.6 mW/m2, and then deduced gradually to 55.6 mW/m2 by the end of Late Miocene. From the Early Pliocene, the value started to rise again and reaches about 57.8 mW/m2 at present. The Liusha?gang source rocks in Bailian sub?sag of Fushan sag entered into oil threshold of Ro=0.5% at about 38×106 a, reaching the hydrocarbon generation peak of Ro=1.0% at about 30×106 a, and at about 20×106 a, it entered into oil threshold of Ro=1.3%. Because the Liushagang source rock’s buried depth is larger, it has much higher maturity and stronger hydrocarbon generation capacity, which could provide abundant oil and gas resources for Fushan sag