A non-volatile memory device including a cell array having memory cells arranged at intersections of word lines and bit lines; an address decoder configured to select one of the word lines in response to an address; a write circuit configured to write program data in memory cells connected with the selected word line; and a control circuit configured to control the address decoder and the write circuit such that a plurality of band program (write) operations are sequentially executed during a write operation, wherein the control circuit is further configured to select each band write operation the optimal write condition of the next band write operation. A plurality of available write conditions are stored as trim information in a plurality of registers. The control circuit selects the register storing information for performing programming under the optimal write condition.