Disclosed is a cluster analysis supporting system, with respect to providing a cluster analysis function, including a cluster analysis service apparatus configured to request a distributed processing service apparatus to perform a k-means clustering based on k values within a predetermined range and a preset iteration frequency until a predefined converge condition is satisfied, and if center values of the k values are calculated from the distributed processing service apparatus, select an optimum center value among the center values, and control calculation and application of an optimum k value through an index calculation with respect to applying clustered indexes assigned based on the selected optimum center value to data, and the distributed processing service apparatus configured to perform the k-means clustering based on the k values and the preset iteration frequency provided from the cluster analysis service apparatus upon the request by the cluster analysis service apparatus.