To provide an electron-emitting device, an electron source, an image-forming apparatus, and a method for manufacturing the electron-emitting device whereby it is possible to reduce a device capacity and a driving voltage, to improve the efficiency of emitting electrons, and to obtain high-resolution beam. The extracting electrode and the cathode electrode are provided on an insulating substrate, a layer having growth selectivity of fibrous carbon is formed on the cathode electrode, and the fibrous carbon is grown via catalyst particles formed on the layer.