The organic matter abundance, type, maturity, gas generation property and intensity of different source rocks in Liaohe Depression are studied. The result shows that the types of proved natural gas are mainly bio-thermo-catalytic transitional zone gas and low temperature pyrolysis gas, while pyrolysis gas and high temperature pyrolysis gas rarely exist, which is not consistent with the thermal evolution degree of source rocks in Liaohe Depression. The depressions where exist high thermal evolution and high hydrocarbon generation intensity should be rich in natural gas with relatively higher maturity. Based on the analysis of deep tectonic settings and reservoir conditions of several important regions, it is supposed that these regions should be in the interior of gas kitchen or directly contact with gas source rocks, thus, they has excellent conditions for reservoir forming and will be the target areas for the further exploration.