Exploration and development of remaining oil in mature oilfields are inevitable trends in the petroleum industry . Drilling cement plugs is a crucial operation in the process of rejuvenating abandoned wells. In order to simulate actual downhole drilling conditions, high-temperature and high-pressure rock drillability testing equipment developed by the State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Engineering at Southwest Petroleum University was utilized. Considering both the hydrostatic pressure and confining pressure, micro-drilling experiments were conducted to assess the drillability of cement plugs at different well depths. The experimental results indicate: (1) The drillability index of cement plugs shows minimal variation with increasing formation pressure. (2) Under normal temperature and pressure conditions, the presence of pores and fractures in the cement plug rock samples reduces drillability, but these factors do not directly affect drillability under different formation pressures at normal temperatures. (3) PDC drill bits can be used for drilling cement plug sections in the process of rejuvenating abandoned wells. These experimental and analytical findings can provide theoretical guidance for the fragmentation and drilling techniques of cement plug drilling during the process of rejuvenating abandoned wells.