Abstract: Northern Jiangsu basin is an extentional basin formed in late cretaceous. Its basement, the strata from Z to K2, experienced three main tectonic stages: Paleozoic passive continental margin, late Paleozoic to early Mesozoic stable subsidence and Mesozoic thrusting. The carbonate strata of Paleozoic and Mesozoic are quite good source rocks for hydrocarbon. Reconstruction of paleo-geotemperature and maturation degree will provide geat value for oil and gas exploration in this area. In this paper, the authors reconstruct the paleo-getempeature and model the hydrocarbon maturation history of Paleozoic. Mesozoic source rocks during the stages of basement evolution and Neocene basin-formation. The calculated maturation degree is in accordance with the practical measuring values of part strata, some new information about source rock maturation is provided for further evaluation of oil-gas prospect in northern Jiangsu area with complicated tectonic evolution.