A method of writing partial page data in a non-volatile memory device includes, reading data from a second block when the size of a last page of data to be written in a page of a first block is smaller than a size of the page of the first block, wherein a size of the read data is given by the size of the page of the first block minus the size of the last page of data; storing together data of the last page and the data read from the second block in a buffer; and writing the data stored in the buffer in the first block.