According to one embodiment, a memory system includes a non-volatile first memory, and a controller. The controller associates a first number of consecutive logical addresses with the first number of physical addresses which are included in a second number of consecutive physical addresses of the first memory. The controller executes a first updating and a second updating. The first updating includes associating a first physical address among the second number of physical addresses with a first logical address. The second updating includes obtaining a second logical address which is away from the first logical address by a value corresponding to distance information on the basis of origin information and the distance information and associating, with the second logical address, a second physical address which had been associated with the first logical address before the first updating is executed.