A multi-layer piezoelectric element comprising: a stacked body comprising: an active section comprising piezoelectric layers and internal electrode layers laminated together, and an inactive section located outside the active section in a stacking direction; an electrically conductive bonding material disposed on a side surface of the stacked body parallel to the stacking direction; and an external electrode plate connected to the side surface of the stacked body with the electrically conductive bonding material interposed therebetween; wherein the external electrode plate comprises: one end extending past the electrically conductive bonding material in the stacking direction, and an area (A) connected to an external circuit on the one end; and characterized in that the electrically conductive bonding material comprises a wider region with a greater width than other regions of the electrically conductive bonding material , at one end thereof closer to the one end of the external electrode plate than to the other end, wherein: a thickness of each of the piezoelectric layers in the active section near a boundary with the inactive section gradually increases as getting closer to the inactive section ; and a boundary between the wider region and the other regions of the electrically conductive bonding material is on the piezoelectric layers having an increased thickness. a stacked body comprising: an active section comprising piezoelectric layers and internal electrode layers laminated together, and an inactive section located outside the active section in a stacking direction; an electrically conductive bonding material disposed on a side surface of the stacked body parallel to the stacking direction; and an external electrode plate connected to the side surface of the stacked body with the electrically conductive bonding material interposed therebetween; wherein an active section comprising piezoelectric layers and internal electrode layers laminated together, and an inactive section located outside the active section in a stacking direction; an electrically conductive bonding material disposed on a side surface of the stacked body parallel to the stacking direction; and an external electrode plate connected to the side surface of the stacked body with the electrically conductive bonding material interposed therebetween; wherein the external electrode plate comprises: one end extending past the electrically conductive bonding material in the stacking direction, and an area (A) connected to an external circuit on the one end; and one end extending past the electrically conductive bonding material in the stacking direction, and an area (A) connected to an external circuit on the one end; and characterized in that the electrically conductive bonding material comprises a wider region with a greater width than other regions of the electrically conductive bonding material , at one end thereof closer to the one end of the external electrode plate than to the other end, wherein: a thickness of each of the piezoelectric layers in the active section near a boundary with the inactive section gradually increases as getting closer to the inactive section ; and a boundary between the wider region and the other regions of the electrically conductive bonding material is on the piezoelectric layers having an increased thickness. a thickness of each of the piezoelectric layers in the active section near a boundary with the inactive section gradually increases as getting closer to the inactive section ; and a boundary between the wider region and the other regions of the electrically conductive bonding material is on the piezoelectric layers having an increased thickness. <EOS>