1. A method of translating a virtual memory address into a physical memory address in an image forming apparatus, the method comprising: requesting an access of a main memory using a virtual memory address by an input/output (I/O) core which controls at least one of functions performed by the image forming apparatus with image data stored in the main memory; translating the virtual memory address requested by the I/O core into a physical memory address using a translation look-aside buffer (TLB) and by predicting the virtual memory address to be requested next by the function core according to an access pattern for the image data of the image forming apparatus; and performing an access corresponding to the image data of the main memory using a translated physical memory address.