The invention discloses a reinjecting twin-well pneumatic shatter auxiliary restoration system and method of underground oil pollution, belonging to the technical field of auxiliary restoration of oil pollution. The system is composed of an indoor part and an outdoor part, wherein, the indoor part comprises a pneumatic shatter unit, a preparation and storing unit for a bacteria liquid, a nutrition adding unit, a reinjecting pipeline of the bacteria liquid, a biphase suction unit and a control unit, and the outdoor part comprises an injecting/shattering well and a seeping well. The in situ bioremediation of the underground oil pollution is realized by utilizing the steps of pneumatic shattering, injecting bacterium, maintaining pressure, reinjecting aeration, pausing and cycling of the system provided by the invention. The system has the advantages of short process flow, compact structure, simple operation and complete realization of automatic control.