A storage apparatus is disclosed which includes: a memory configured to have a plurality of pages to which data can be written in units of a page, the memory being further configured to have a plurality of pages of write data stored into each page in multi-valued form; and a control section configured to select pages to which to write the data from among the plurality of pages of the memory, the control section being further configured to write to the selected pages of the memory the data of at least two bits in multi-valued form for a plurality of pages including the selected pages; wherein, when writing the plurality of pages of the write data, the control section puts the write data into multi-valued form per page before writing the data to a plurality of different unused pages of the memory on a page-by-page basis.