Provided are a method and apparatus for driving a PDP for widening a driving margin and improving contrast. The method for driving a PDP includes a first step of forming wall charges in cells with a set-up discharge using a set-up signal in a first sub-field and erasing the wall charges with a set-down discharge using a first set-down signal to initialize the cells, and a second step of erasing the wall charges with a set-down discharge generated using a second set-down signal different from the first set-down signal in a second sub-field, to initialize the cells. The method and apparatus for driving a PDP uniformly initialize sub-fields to widen the driving margin of PDP and remove a set-up discharge in at least one sub-field to improve the contrast of PDP.