A semiconductor storage device includes a stack, a channel layer, a first charge storage portion, and a second charge storage portion. The stack includes a plurality of conductive layers and a plurality of insulating layers, and the plurality of conductive layers and the plurality of insulating layers are alternately stacked one by one in a first direction. The channel layer extends in the first direction in the stack. The first charge storage portion is provided between the channel layer and each of the plurality of conductive layers in a second direction intersecting with the first direction. The second charge storage portion includes a portion interposed between two adjacent conductive layers in the plurality of conductive layers in the first direction.