According to one embodiment, a nonvolatile semiconductor memory device includes a first memory string including a first memory cell and a second memory cell aligned along a first axis, a source contact provided at a source-side end of the first memory string, a second memory string that extends along the first axis and includes a third memory cell that aligns with the first memory cell along a second axis perpendicular to the first axis, and a shield conductive layer. The shield conductive layer extends along the first axis between the first memory string and the second memory string and is electrically connected to the source contact.