It aims to improve electron emission efficiency in an electron beam apparatus which includes laminated electron-emitting devices. To achieve this, there are provided an insulating member which has a concave portion on its surface, a cathode which is positioned astride a side surface of the insulating member and an inner surface of the concave portion, a gate which is positioned opposite to the cathode, and a protruding portion which is formed on the gate. In this constitution, the low potential surface of the cathode which is positioned inside the concave portion is inclined to the side of the gate from the entrance toward the interior of the concave portion.