A method for programming at least one memory cell of a plurality of memory cells included in a non-volatile memory device, the at least one memory cell including a word line and a bit line, the method including: performing a first and second program and verify operation based on a first and second condition, respectively, wherein each program and verify operation includes generating a program voltage and a bit line voltage by a voltage generator included in the non-volatile memory device and providing the program voltage and the bit line voltage to the word line and the bit line, respectively, wherein voltage levels and voltage application times of each program voltage and bit line voltage correspond to the first condition or the second condition, respectively, wherein the first condition is different from the second condition.