A method of controlling a shared memory and a user terminal controlling the operation of the shared memory are disclosed. The portable terminal according to an embodiment of the present invention has a memory unit with a storage area partitioned to blocks in a quantity of n and a plurality of processors reading or writing data by accessing a partitioned block. At least one of the partitioned blocks is assigned as a common storage area, accessible by a processor having an access privilege, and the processor having the access privilege performs an operation of maintaining the data stored in the common storage area. With the present invention, the common storage area can be accessed by a plurality of processors, and thus the data transmission time between the processors can be minimized.