The magnetic properties investigated by experiment on the Ni/NiO interface of Ni/NiO multi-thin layers and surface-NiO-coated Ni ultra fine particles are reported. At temperatures below 80 K, an abnormal enhanced magnetization under external magnetic field (H = 40kOe) was found. The enhanced magnetization decreases quickly with temperature increasing.The high field (5-65 kOe) magnetization (approching to saturation) of ultrafine particles and multi-thin layers were also measured. The fit results for experimental data indicate that the interface Ni/NiO in Ni/NiO UFP and Ni/NiO ML have inhomogenous spin structure.