A liquid discharge head comprising: a substrate including a pressure chamber ; an actuator including a driving element configured to apply pressure to liquid in the pressure chamber ; and a channel member including a supply channel configured to supply the liquid to the pressure chamber , wherein the actuator includes: a first film arranged on the substrate to cover the pressure chamber ; and a second film arranged on an opposite surface of the first film , the opposite surface being opposite to the substrate , wherein the substrate and the channel member are attached to each other with an adhesive in a state that the first film and the second film are sandwiched between the substrate and the channel member , wherein a first through hole is located in a part of the first film at which the pressure chamber and the supply channel are overlapped in a stacking direction of the first film and the second film , wherein a second through hole is located in a part of the second film at which the the first through hole is overlapped in the stacking direction, wherein the edge of the first through hole is positioned inward of the edge of the second through hole , and wherein the adhesive is applied to a part of the opposite surface of the first film at which the second through hole is overlapped in the stacking direction, so as to cover a boundary part between the first film and the second film , characterized in that : a thinned portion is formed in the part of the opposite surface of the first film , and a length, in the stacking direction, of the thinned portion is smaller than a length, in the stacking direction, of a part of the first film at which the second film is overlapped in the stacking direction. a substrate including a pressure chamber ; an actuator including a driving element configured to apply pressure to liquid in the pressure chamber ; and a channel member including a supply channel configured to supply the liquid to the pressure chamber , wherein the actuator includes: a first film arranged on the substrate to cover the pressure chamber ; and a second film arranged on an opposite surface of the first film , the opposite surface being opposite to the substrate , a first film arranged on the substrate to cover the pressure chamber ; and a second film arranged on an opposite surface of the first film , the opposite surface being opposite to the substrate , wherein the substrate and the channel member are attached to each other with an adhesive in a state that the first film and the second film are sandwiched between the substrate and the channel member , wherein a first through hole is located in a part of the first film at which the pressure chamber and the supply channel are overlapped in a stacking direction of the first film and the second film , wherein a second through hole is located in a part of the second film at which the the first through hole is overlapped in the stacking direction, wherein the edge of the first through hole is positioned inward of the edge of the second through hole , and wherein the adhesive is applied to a part of the opposite surface of the first film at which the second through hole is overlapped in the stacking direction, so as to cover a boundary part between the first film and the second film , characterized in that : a thinned portion is formed in the part of the opposite surface of the first film , and a length, in the stacking direction, of the thinned portion is smaller than a length, in the stacking direction, of a part of the first film at which the second film is overlapped in the stacking direction. a thinned portion is formed in the part of the opposite surface of the first film , and a length, in the stacking direction, of the thinned portion is smaller than a length, in the stacking direction, of a part of the first film at which the second film is overlapped in the stacking direction. <EOS>