The invention discloses an accurate load control method for coping with power source off-grid impact and calculating unit adjustment capability, and belongs to the technical field of electrical power systems and automation thereof. According to the method, on the premise of sufficiently calculating adjustment capability of own power grid operation units of some regional power grids or large-scale industrial and mining enterprises, whether to take emergent control measures or not is judged according to loss of the units, and load shedding objects are selected accurately according to load operation power when it is needed. The accurate load control method has the advantages that accuracy and effectiveness of the control measures of safe and stable control devices are guaranteed, operation reliability of the power grids in a fault or special mode is improved, and no-voltage risks of the power grids are reduced.