A nonvolatile semiconductor storage device includes a memory cell array including a plurality of memory cells arranged at intersection positions of word lines and bit lines in a matrix form, and a row decoder including a row sub-decoder to which a lower address for selecting a word line is input, wherein one unit of the row sub-decoder for selecting one word line is constituted of a first transistor of a first conduction type, and a second transistor of a second conduction type, and a gate electrode of each of the first and second transistors is arranged in a direction in which the bit lines are arranged.