Abstract: Basin modeling describes the evolutions of basin structure, deposition as well as hydrocarbon generation, migration and accumulation from both time and space aspects by using computer software based on physical and chemical principles of petroleum geology, by which oil and gas resources can be estimated. TSM basin simulation is a deterministic numerical simulation software system constrained by basin prototype and guided by a basin research program of "3T-4S-4M". The histories of burial, thermal evolution, hydrocarbon generation, migration and accumulation were simulated by using a deterministic hydrocarbon response simulation module and guided by the parallel and superposed analyses of basin prototype, in order to reasonably estimate hydrocarbon resources. This theory was applied in the West Sichuan Depression and revealed that basin prototype changed from continental margin depression to foredeep basin ever since the late Triassic. And the source rock generation, distribution and evolution characteristics as well as the hydrocarbon generation, migration and expulsion of the Upper Triassic Xujiahe Formation were also illustrated. Simulation results showed that the subsidence of depression during Jurassic was an important reason for the difference of hydrocarbon generation and discharge in various formations. The final structure in the middle-late Jurassic epoch controlled natural gas migration and accumulation, and formed two favorable resource gathering areas, Xiaoquan-Fenggu and Anxian-Duck River-Dayi, reflecting the controlling on hydrocarbon generation and accumulation by prototype basin superposition. This application showed that TSM basin simulation reveals dynamically the oil and gas evolution, which means "prototype controlled sources, superposition controlled accumulation", and predicts undiscovered oil and gas by fitting with the known. TSM software is an important technology and tool in the field of oil and gas exploration.