The magnetic properties of two kinds of alloys (Ni-Pe-Nb and Ni-Pe-Nb-Al) after various heat-treatments are studied. The initial and maximum permeabilities are high and can be compared with those of the technical Mo-permalloys. Some of the physical parameters of Ni-Pe-Nb and 4Mo-permalloy are tabulated here for comparison.The quaternary Ni-Pe-Nb-Al alloy possesses higher Vickers hardness and electrical resistivity. Curves of a. c. magnetic permeabilities of the Ni-Pe-Nb-Al alloy specimens are presented.In the specimens of Ni-Pe-Nb-Al after slow cooling from high temperature, modulated structures are developed with a wave-length of about 160?. Eapid cooling from 970℃ suppresses the formation of the modulated structure. The material with a modulated structure possesses higher hardness as well as higher coercive force.