The invention is a Fe—Ni alloy material comprising Ni: 26-37 wt %, Si: 0.001-0.2 wt %, Mn: 0.01-0.6 wt %, Al: 0.0001-0.003 wt %, Mg: not more than 0.001 wt %, Ca: not more than 0.001 wt % and the reminder being Fe and inevitable impurities, and containing not more than 0.02 wt % of one or more MnO—SiO₂—Al₂O₃ inclusion, SiO₂ inclusion and MgO—Al₂O₃ inclusion insoluble in an aqueous solution of ferric chloride, and is to provide electronic materials for shadow mask and the like having a good hole shape in an etching treatment and a high quality.