An advantage of the application is to provide a magnetoresistance element capable of increasing a plateau magnetic field Hp1 while maintaining high ΔRA. A magnetic layer 4c1 adjacent to a non-magnetic material layer 5 in a second fixed magnetic layer 4c constituting the fixed magnetic layer 4 is formed of a first Heusler-alloy layer represented by Co2x(Mn(1-z)Fez)xαy (where the element α is any one element of 3B group, 4B group, and 5B group, x and y all are in the unit of at %, 3x+y=100 at %). Additionally, the content y is in the range of 20 to 30 at % and a Fe ratio z in MnFe is in the range of 0.2 to 0.8. Accordingly, the plateau magnetic field Hp1 may increase while maintaining high ΔRA.