A control device including: a storage device that includes a first storage area including a plurality of blocks into which data can be written more than once and a second storage area into which data can be written only once, wherein the first storage area further stores a flag for each of the blocks, the flag indicating whether or not the block is allowed to be used; a flag management information creation unit configured to create, on the basis of the flag, a flag management information for managing whether or not data can be stored in each block of the storage device; and a management information controller configured to cause the flag management information to be stored in the second storage area.