To provide a magnetic device which is excellent in stability of a hard layer, has higher density, and is easy to form, in a CPP type GMR device.

In this magnetic device, a fine porous layer is formed on a substrate, and ferromagnetic layers and nonmagnetic layers are laminated on a part or the whole of the fine porous layer. The device is used by applying a current in the axial direction of the fine porous layer. A hard layer 15 has a laminated structure where plural ferromagnetic layers 16, 17 have antiferromagnetic coupling via nonmagnetic layers 18. In the laminated structure of the fine porous layers, the hard layers 15 and free ferromagentic layers 14 are laminated via nonmagnetic layers 19, thereby constituting the magnetic device. The solid magnetic storage device is provided with this magnetic device.