A multi-layer piezoelectric element of high durability wherein the internal electrodes and the external electrodes do not break even when operated continuously over a long period of time under high electric field and high pressure is provided. The first multi-layer piezoelectric element according to the present invention comprises a stack formed by stacking piezoelectric layers and internal electrodes alternately one on another and external electrodes formed on a first side face and on a second side face of the stack, wherein one of the adjacent internal electrodes is connected to the external electrode formed on the first side face and the other internal electrode is connected to the external electrode formed on the second side face, and the external electrodes include an electrically conductive material and glass and is formed from a porous electrically conductive material that has a three-dimensional mesh structure.