NONVOLATILE SEMICONDUCTOR STORAGE DEVICE

PROBLEM TO BE SOLVED: To provide a nonvolatile semiconductor storage device which enables reduction in chip size.SOLUTION: A nonvolatile semiconductor storage device comprises: a memory cell array 11 in which a plurality of memory cells each arranged at a position where a bit line and a word line cross; a sense amplifier 14 for reading data stored in the memory cell through the bit line in a reading operation; a switching transistor ST1-1 which is arranged between the memory cell array 11 and the sense amplifier 14 and electrically connected to between the first bit line and the sense amplifier 14, and has a first channel width; and a switching transistor ST2-1 which is arranged between the memory cell array 11 and the sense amplifier 14 and electrically connected to between the second bit line and the sense amplifier 14, and has a second channel width different from the first channel width.