A magnetoresistive effect element includes a TMR element disposed at an
intersection where a bit line and a write word line intersect, in a
manner sandwiched between the bit line and the write word line, and is
configured such that it includes a sensitive magnetic layer whose
magnetization direction is changed by a synthetic magnetic field of
magnetic fields generated around the bit line and the write word line,
and at the same time such that electric current flows in a direction
perpendicular to the laminating surfaces thereof, and a magnetic material
individually covering the bit line and the write word line at the
intersection, thereby forming an annular magnetic layer associated with
the bit line and an annular magnetic layer associated with the write word
line.