The invention relates to a method and a device for determining the priority of a reactive power regulation object of a wind power plant group. The method comprises the steps of: dividing reactive power regulation objects into two types according to the voltage of each reactive power regulation object in a wind power plant group, and determining the priority between the two types of reactive powerregulation objects; determining the priority between various types of reactive power adjusting objects according to the sensitivity of each reactive power adjusting object; and selecting a high-priority reactive power regulation object for reactive power regulation in the reactive power regulation control process until the grid-connected point voltage of the wind power plant group returns to normal. according to the invention, the priority of each reactive power regulation object of the wind power plant group is determined through the voltage and the sensitivity of each reactive power regulation object of the wind power plant group, so that the reactive power regulation objects of the wind power plant group can quickly support the voltage change of a power grid in the reactive power control process, and the economical efficiency and the rapidity of the reactive power regulation objects of the wind power plant group are improved.