A non-volatile semiconductor memory device includes: a memory cell array in which electrically rewritable floating gate type memory cells are arranged; and a plurality of sense amplifier circuits configured to read data from the memory cell array, wherein each the sense amplifier circuit is configured to sense cell data of a first memory cell selected from the memory cell array under a read condition determined in correspondence with cell data of a second memory cell adjacent to the first memory cell and written after the first memory cell.