An electron-emitting device and a fabricating method thereof are provided. First, a substrate, having a first side and a second side which is opposite to the first side, is provided. Afterwards, a first electrode pattern layer is formed on the first side of the substrate. Next, a conductive pattern layer is formed on the substrate and the first electrode pattern layer. After that, an electron-emitting region is formed in the conductive pattern layer. Then, a second electrode pattern layer is formed on the second side of the substrate and partially covers the conductive pattern layer. The fabricating method has a simple fabricating process and a low fabricating cost.