When performing a program operation, a non-volatile memory device comprising a multi-plane performs a cache write operation by employing a page buffer circuit of a plane that does not perform the program operation. A data line mux transfers an externally input first data to a page buffer unit of a plane, which will be programmed, according to a plane select signal, transfers a second data to a page buffer unit of a plane on which a program operation is not performed, while the program of the selected plane is performed, and after the first data is programmed, provides a data transfer path between one page buffer unit and the other page buffer unit according to a data transfer control signal.