In order to select the initial clustering centers for the divisional clustering algorithm such as the ??-means algorithm, the sample density calculating regions number of each dimension is confirmed according to the samples number and their values, firstly. Then, the average value of the samples of the region with peak value satisfying the filtering conditions is taken as the candidate for the initial clustering center, and a relationship tree of the candidates is established on the mapping relations of the regions. Furthermore, the initial clustering centers are selected by using the maximal-minimal distance algorithm. To confirm the best number of the clusters, a clustering quality evaluation function is established according to the sample density and cluster density. Experiment results of the manual and UCI data sets show the effectiveness of the proposed algorithms.