The invention discloses an electricity utilization demand identification method of power major-customers. The method comprises: collecting demand information of the to-be-identified major customers, and carrying out hierarchical classification processing on the demand information; extracting evaluation indexes of the to-be-identified major customers and corresponding evaluation index data in a statistical cycle, classifying the to-be-identified major customers on the basis of an improved K-means clustering algorithm, and extracting electricity utilization characteristics of each type of the major customers; and carrying out matching on the electricity utilization characteristics of the major customers and the corresponding demand information, and identifying concerned demands of each type of the major customer. According to the method, the demands of the major customers are extracted and layered, the improved K-means clustering algorithm is used to subdivide the major customers, and demand layering and customer subdivision are combined to identify the specific concerned demands of each type of major customer groups.