A memory device including a normal memory cell array including a first magneto-resistance memory cell that is connected to a first bit line, a first source line, and a first word line, and configured to receive a selection voltage through the first word line, a monitor memory cell array including a second magneto-resistance memory cell that is connected to a first signal line and a second signal line, a gate of a cell transistor of which is configured to receive a non-selection voltage, and a body bias generator configured to sense a leakage current flowing through the first signal line and control a body voltage provided to each of a body of a cell transistor of the first magneto-resistance memory cell and a body of the cell transistor of the second magneto-resistance memory cell based on the leakage current may be provided.