The study on petroleum expulsion is one of the weakest issues in the field of petroleum geochemistry. However, expulsion efficiency is a key parameter to evaluate the conventional and unconventional oil and gas resources. There are still serious debates to date on this issue and no agreement on the generation and expulsion efficiency and corresponding model within geological frame in terms of different types of organic matter. In this paper, using more than 15000 data points, the dynamics of hydrocarbon generating potential along the maturity sequence in natural profiles from source rocks deposited in four large lacustrine sedimentary basins (the Bohai Bay basin, the Songliao basin, the Ordos basin and the Junggar basin) and nine middle-small lacustrine oil-enriched basins/depressions were investigated to construct the general model in respect to the generation and expulsion efficiency for lacustrine source rock. Whatever the petroliferous basin is, the large lacustrine sedimentary basins, the middle-small lacustrine fault basins, or the salt lake basins, there is almost a similar character in terms of hydrocarbon generation and expulsion. The efficiency of petroleum expulsion will increase with increasing maturity of lacustrine source rocks. There is a low efficiency of petroleum expulsion at the low mature stage and reaches a high efficiency at the highly to over mature stage. For source rocks with type I and II organic matter, they share the same expulsion model. The relative expulsion efficiency is lower than 45% at the stage of low maturity, whereas it reaches up to 85%-90% at the peak oil stage. Once into the post peak oil stage, the relative expulsion efficiency can be great than 90%. The accumulated expulsion efficiency is less than 10% at the the stage of low maturity, and about 50%-60% at the peak of the oil window, whereas it reaches 75%-85% at the end of the oil window. Therefore, the main expulsion stage for source rocks with type I and II organic matter corresponds to the equivalent vitrinite reflectance of 0.7% to 1.2%, most of hydrocarbon generated were expelled from source rock within oil window. As to lacustrine source rocks with type III organic matter, their expulsion efficiency is lower than that of source rocks with type I and II organic matter. The accumulated expulsion efficiency is about 50% at the the oil window. Its main expulsion stage corresponds to the equivalent vitrinite reflectance of 0.8% to 2.0%. Factors controlling the expulsion magnitude and efficiency are total organic carbon, organic types and maturity of source rock. There is no significant influence on the expulsion magnitude and efficiency in terms of basin types, development of faults, source rock depositional environments and the quality of porosity and permeability in connected conduits.