A method for programming a non-volatile memory in a programming operation is provided. The non-volatile memory has a number of cells and each of part of the cells stores data having at least 2 bits at least corresponding to a first page and a second page. The first programming-verifying operation including programming the first page and verifying whether the first page is successfully programmed is performed. When a first original fail-bit number for the first page is more than a predetermined fail-bit value, a second programming-verifying operation to the first page is performed to obtain a first over-counting fail-bit number for the first page and reduce the first original fail-bit number by the first over-counting fail-bit number. When the reduced first original fail-bit number is not more than the predetermined fail-bit value, the first page is set as successfully programmed.