Provided are memory devices and memory programming methods. A memory device may include: a multi-bit cell array that includes a plurality of memory cells; a controller that extracts state information of each of the memory cells, divides the plurality of memory cells into a first group and a second group, assigns a first verify voltage to memory cells of the first group and assigns a second verify voltage to memory cells of the second group; and a programming unit that changes a threshold voltage of each memory cell of the first group until the threshold voltage of each memory cell of the first group is greater than or equal to the first verify voltage, and changes a threshold voltage of each memory cell of the second group until the threshold voltage of each memory cell of the second group is greater than or equal to the second verify voltage.