A Ni—Fe based alloy powder of the present invention contains not less than 90% by a combined mass of Ni and Fe and homogeneously has particles having an average particle diameter from 0.1 to 1 μm, and an average value of mass ratio Fe/(Fe+Ni) from 15% to 25% both inclusive, wherein the ratio of a maximum value X and a minimum value Y of Fe/(Fe+Ni), which are found at individual points in the region ranging from the center of any particle of the alloy powder to locations apart by 0.9 fold of the particle radius therefrom, X/Y is from 1 to 2. By producing a sintered part using this Ni—Fe based alloy powder as a raw material powder, it is possible to obtain electronic circuit parts which are homogenous and have high magnetic permeability.