A page buffer of a nonvolatile memory device according to the present disclosure comprises a first data latch unit configured to store data for program or program inhibition, a second data latch unit configured to store data for setting threshold voltage states of cells to be programmed, and a 1-bit pass determination unit configured to determine whether a cell to be programmed has been programmed to exceed a verification voltage by grounding or making floating a first verification signal output terminal in response to data set to a first node of the first data latch unit and data applied to a sense node.