Non volatile memory device and program method thereof

PURPOSE: A non-voltage memory device and a programming method thereof are provided to prevent a program disturbance and pass disturbance by providing a variable pass voltage and a precharge voltage according to a level of program voltage. CONSTITUTION: A level of a program voltage is detected(S20). According to the level of the program voltage, the precharge voltage of a bit line and non-selective word line voltage are controlled. The level of the program voltage is detected by referring to the target program state where selected memory cells are programmed(S30). The level of the program voltage is detected by referring to the size of the program step number corresponding to the program voltage. The level of the program voltage is detected by referring to the result of the verification read. The program voltage is increased for reprogram(S50).