Aiming to solve problems about complex faulted structure and rule of oil-gas migration and accumulation, we have studied the fault connecting properties in Qingcheng arch and the Mesozoic key faults’ability to plug or transport hydrocarbon. Based on the study, the numerical simulation has been carried out on oil migration and accumulation, finding that Mesozoic dominant migrating pathways are westward and west-southward along the Gaoqing fault. The direction of oil-gas migration is mainly controlled by structure modality and reservoir sandstones. Oil and gas migrate to the back of structure nose along the fault and sandstones and the migration distance is controlled by the structure nose with a northeast strike. However, it is difficult for oil and gas to keep on migrating to the west because the western side of strata is inclining to the west. So, oil and gas can migrate easily on the west of the nose structure along the Gao15 well-Gao52 well-Gao46 well in Mesozoic, which means this area is an effective petroliferous area. Thus we can know the direction of oil and gas migration and the development area of trap as well as the characteristics of Mesozoic reservoirs.