According to one embodiment, a nonvolatile semiconductor memory device includes a first interconnect, a second interconnect and a resistance change layer. The first interconnect extends in a first direction on a major surface of a substrate. The second interconnect extends in a second direction non-parallel to the first direction. The resistance change layer includes a conductive nanomaterial, the resistance change layer located between the first interconnect and the second interconnect and being capable of reversibly changing between a first resistance state and a second resistance state by a voltage applied or a current supplied through the first interconnect and the second interconnect. The resistance change layer has a density varied along a third direction generally perpendicular to the first direction and the second direction.