A nonvolatile memory device includes a memory cell array including first to fourth planes, a page buffer circuit that includes first to fourth page buffer units connected with the first to fourth planes, respectively, an input/output circuit that includes a first input/output unit connected with the first to fourth page buffer units and a second input/output unit connected with the second and fourth page buffer units, and control logic that controls the input/output circuit to output first data from one of the first to fourth page buffer units through the first input/output unit in a first read mode and output second data from one of the first and third page buffer units through the first input/output unit and third data from one of the second and fourth page buffer units through the second input/output unit in a second read mode.