The present invention provides a method for managing memory space in an electronic device including: selecting a candidate page from a first memory space for swapping the candidate page out of the first memory space into the second memory space; compressing the candidate page to obtain a first compressed page and a first hash value of the first compressed page; performing a comparison using the first hash value of the first compressed page and the hash values of the pages stored in a second memory space to find whether the pages have the same content as the first compressed page or the candidate page; and if a page is found to have the same content as the first compressed page or the candidate page, mapping a virtual address of the first compressed page or the candidate page to the found page.