A method for accessing files on a storage system is provided. A hash memory table including a plurality of hash buckets respectively corresponding to a plurality of index hash codes is built. Each of the hash buckets has a pointer pointing towards at least one entry. Each of the entries has a physical address field and a hash code field. The physical address fields respectively record physical addresses storing the files, and the hash code fields respectively record verification hash codes corresponding to the files. The index hash codes are generated by inputting keys of the files to an index hash function and the verification hash codes are generated by inputting keys of the files to a verification hash function. Then, the hash memory table is loaded into the buffer with a bucket-based replacement policy so that the files are able to be accessed according to the hash memory table.