A memory device includes a memory cell array that includes memory cells, a row decoder that is connected to the memory cell array through word lines, a column decoder that is connected to the memory cell array through bit lines and source lines, a write driver that transfers a write voltage to a bit line, which is selected by the column decoder, from among the bit lines by using a gate voltage in a write operation, and control logic that generates the gate voltage. The gate voltage is higher than the write voltage.