The invention discloses an extra-high voltage direct current connected provincial level power grid partitioning optimization operation control method. According to the frequency and voltage characteristic of a partitioning power grid after a receiving end power gird partitioning isolated grid is formed, and after power safety liability accident risk is taken into consideration, whether a measure in combination of prevention and control and low frequency low voltage de-loading and emergency control and low frequency low voltage de-loading can solve the frequency and voltage problem or not afterisolated grid is formed is determined; if the problem can be solved, the safety and stability problem of the isolated grid is solved by the measure in combination of prevention and control and low frequency low voltage de-loading and emergency control and low frequency low voltage de-loading; if the problem cannot be solved, optimized partitioning is carried out, and the partitioning power receiving proportion is limited within a range when the safety and stability problem of the isolated grid can be solved by the measure in combination of prevention and control and low frequency low voltagede-loading and emergency control and low frequency low voltage de-loading, so that the power safety accident liability caused by solving the frequency and voltage problem through load shedding after the receiving end power gird partitioning isolated grid is formed can be effectively lowered or eliminated.