A memory device includes a first nonvolatile memory including a resistive memory cell; and a controller. The controller may be configured to provide the first nonvolatile memory with a first data, a first program command, and a first address. The controller may be configured to receive a second data, which is a verify read from the resistive memory cell programmed with the first data, from the first nonvolatile memory in response to the first program command. The controller may be configured to compare the first data with the second data to detect a number of fail cells. When the number of detected fail cells is greater than a reference value, the controller may be configured to generate a third data obtained by inversing the first data, and provide the third data to the first nonvolatile memory. The first data may include an inversion flag bit.