How to read the NAND flash memory device

A read method of a NAND flash memory device, and applying a bit line voltage for read to a bit line of the selected cell. It is applied to the selected cell, a read voltage to a word line of the selected cell. And applying a first read voltage to the word line of the first non-selected cell is not located in adjacent two sides and the selected cell. The word line of the second non-selected cell which is located adjacent both sides and the selected cell, is applied to a second reading voltage lower than the first reading voltage. The string selection line and the ground selection line connected to the string of the selected cell, and a voltage is applied. Next, by comparing the electric signals output through the string including the selected cell and the reference signal and determines the data of the selected cell. According to the above method, interference is reduced by the non-selected neighboring cells can be read out the correct data in the selected cell.