A method for performing a hard hand-off between service areas in a cellular mobile communication system is provided. The method for performing a hard hand-off according to the invention includes the steps of setting an area of services covered with a frequency assignment (FA) unavailable to adjacent stations to be a boundary cell, entering into the set boundary cell by a mobile communication terminal during communication, and searching FAs of adjacent stations excluding the base station currently engaged in communication with said mobile communication terminal so as to determine a target FA, with which the mobile communication terminal is to perform a hard hand-off. The method for performing a hard hand-off according to the invention can prevent deterioration of call qualities caused by unnecessary hard hand-offs, and reduce the load on a system.