The invention relates to an optimal selection method for a power quality energy-saving and efficiency-improving scheme of a power distribution network. The method comprises the following steps: firstly, dividing a network into sub-regions by adopting a Kmeans clustering method; determining an optimal distribution point of the power quality treatment device through SI indexes (stability indexes) ineach sub-region, and then performing quantitative calculation on energy-saving potential after comprehensive treatment of the quality of the power distribution network by considering two targets of power quality treatment, namely loss reduction quantity and economy; and aiming at the problem that target functions in multi-target optimization often conflict with each other, carrying out multi-target optimization, and finally, forming a power quality control optimization scheme. According to the invention, power distribution network partitioning and point distribution considering the electricaldistance are realized; and the energy-saving and loss-reducing effects of the power distribution network are improved.