The embodiment of the invention provides a method and a device for dividing a cell cluster. The method comprises the following steps: calculating the business relevance between cells according to relevance statistical data between the cells, and finding maximum connected clusters, wherein the cells in each maximum connected cluster have strong relevance and the cells between the maximum connected clusters have weak relevance; when one cell belongs to multiple maximum connected clusters, attributing the cell to a unique cell cluster; according to geographical location information, merging cell clusters of which the scales are smaller than a cluster scale threshold to obtain the cell cluster which contains the cells according with the cell quantity threshold. According to the method and the device disclosed by the invention, the stable cell cluster which has a business sharing function and a reasonable scale is obtained by dividing each cell according to common network data and the cluster scale threshold so as to ensure that the multi-purpose cell cluster scale is controllable, and the cell cluster can be used for estimating whether the structure of a communication network is reasonable, whether the LAC (Location Area Code) boundary/BSC (Base Station Controller) boundary is reasonably divided, whether the frequency allocation is reasonable, and the like in subsequent works.