A memory package in which a plurality of stacked non-volatile memory dies is connected to one another through a plurality of vertical vias is used in a memory system. The dies are classified into a plurality of die groups including a first die group that includes a plurality of dies connected to a first channel, and a second die group that includes a plurality of dies connected to a second channel. A data write/read operation on the first die group is performed through the first channel in response to an I/O command designating a first area corresponding to the first die group, and a data write/read operation on the second die group is performed through the second channel in response to an I/O command designating a second area corresponding to the second die group.