According to one embodiment, a storage device includes a nonvolatile memory and a controller. The controller includes a host interface control circuit and a memory interface control circuit. When, within a period during which the controller is in a mode to manage mapping between logical addresses and physical addresses of the nonvolatile memory in units of management size corresponding to plural clusters, a skip write command with a skip mask indicating logical blocks to be transferred is received from a host, the host interface control circuit transfers write data to a buffer in units of clusters, and transmit plural write instructions to the memory interface control circuit when the cluster being currently transferred is the last valid cluster in the plural clusters.