The invention discloses a method and a system of dividing a multicast/broadcasting service area. The method comprises the following steps: collecting and receiving the locating information of a mobile station MS of the multicast/broadcasting business and the multicast/broadcasting business service; forming an MS distribution map of receiving the multicast/broadcasting business service according to the locating information of the MS; and comparing the MS distribution map with the multicast/the broadcasting service area, and adjusting the current multicast/broadcasting service area programming according to the MS distribution map when the programming of the current multicast/broadcasting service field is not reasonable. The invention has the advantages of enhancing network service capacity and improving the user experience.