The invention relates to a reading and writing method and device for a counter. The method comprises the steps of: receiving an operation request, wherein the operation request comprises an address ofa first storage page; acquiring counter information stored in the first storage page and a second storage page, wherein the counter information comprises a sequence number, a check value and a counter value, and the second storage page is a next storage page of the first storage page in a FLASH chip, which corresponds to the counter; according to the counter information stored in the first storage page and the second storage page, determining an active storage page; and according to the operation request and the counter information in the active storage page, executing operation processing corresponding to the operation request. According to the reading and writing method and device for the counter, which are provided by the invention, power-off protection on the counter information can be implemented, repeated operations required by a backup operation are reduced, and a reading and writing rate of the counter is improved.