a magnetic memory device capable of preventing the structure of an amplifier from complication and performing high - speed reading is obtained . this magnetic memory device comprises a memory cell consisting of a storage element exhibiting ferromagnetic resistance and a transistor connected to the storage element , a word line connected to a control terminal of the transistor , a bit line connected to a first end of the storage element through the transistor , a reference bit line connected in common for a plurality of bit liens and an amplifier connected to the bit line and the reference bit line . the magnetic memory device reads potential difference caused between the bit line and the reference bit line with the amplifier in data reading .