A TMR device comprising an antiferromagnetic layer made of an antiferromagnetic material containing Mn, a magnetization fixed layer made of a ferromagnetic material, a tunnel barrier layer made of a dielectric material, and a magnetization free layer made of a ferromagnetic material. An insulator material layer is inserted in the magnetization fixed layer at a distance from the antiferromagnetic material layer and the tunnel barrier layer. One material can be expressed by NX, where X is a first element selected from the group consisting of oxygen, nitrogen and carbon; and N is a second element, provided that the bonding energy between the first and the second elements is higher than the bonding energy between manganese and the first element. A second material can be expressed by MX, where M is an element selected from the group consisting of titanium, tantalum, vanadium, aluminum, europium, and scandium; and X is an element selected from the group consisting of oxygen, nitrogen and carbon. The tunnel magnetoresistance effect device suppresses the diffusion of Mn from the Mn based alloy constituting the antiferromagnetic material layer even after heat treatment is performed.