The invention relates to the electric energy quality comprehensive assessment, aims at providing an electric energy quality comprehensive assessment method of a distributed generating system and a micro power grid. The method comprises the following steps of: monitoring synchronized grid public coupling points to obtain monitoring data of each electric energy quality index; normalizing the data by using a maximin method; establishing a hierarchy assessment model and defining a corresponding sudden-change decision model; and obtaining the sudden-change grade of each layer from the lower layer to the top layer according to the sudden-change decision model, and finally obtaining the sudden-change grade of each synchronized grid public coupling point, that is, the electric energy quality comprehensive assessment index, wherein the greater the value is, the higher the grade of the corresponding electric energy quality is. The method provided by the invention has simple computation process and considers the nonlinear factor in the system, can provide the quantized index and basis for a power grid operator who fixes a price of the power to a distributed generating party according to the quality, and provides a reference target for the electric energy quality management. A corresponding compensating device can be mounted on the basis of the assessment method so as to flexibly customize the electric energy quality of the micro power grid.