To provide a nonvolatile semiconductor storage device having high controllability, and provide a manufacturing method of the nonvolatile semiconductor storage device.

A nonvolatile semiconductor storage device comprises: a first memory cell array layer; a first insulation layer formed on the first memory cell array layer; a second memory cell array layer formed on the first insulation layer; a control gate formed via an inter-gate insulation layer, on both lateral faces in a first direction of first and second floating gates vertically positioned via a first insulation layer, and extending in a second direction orthogonal to the first direction; and an auxiliary gate formed via the inter-gate insulation layer, on both lateral faces in the first direction of the first and second floating gates vertically positioned via the first insulation layer, and extending in the second direction, and forming an auxiliary transistor together with first and second semiconductor layers and first and second gate insulation layers.