An optical disc apparatus is provided with optimum power control (OPC) to determine an optimum laser power needed for recording data on an optical disc. Such an apparatus comprises a controller to determine optimum writing power in such a way of re-establishing a new test zone when an erasing error is detected on an initially established test zone in order to perform the OPC. When the erasing error is detected on a test zone of an OPC zone, a new test zone is re-established, so that OPC is performed rapidly while reducing an error frequency occurring when optimum writing power is not determined.