Non-volatile memory device and programming method thereof

A non-volatile memory device comprising:

• a memory cell array including memory cells respectively connected to bit lines;
• and
• a control logic unit configured to control a program operation with respect to the memory cells, wherein the control logic unit is further configured to:
• perform a normal program verify operation with respect to the memory cells by using a normal program verify condition, during the program operation, and
• based on a suspend command that is received during the program operation, perform an initial program verify operation with respect to the memory cells by using an initial program verify condition that is different from the normal program verify condition,
• wherein the normal program verify condition comprises a normal program verify voltage, and
• the initial program verify condition comprises an initial program verify voltage that is different from the normal program verify voltage.