A method of making a microstructure with thin wall portions (T1-T3) includes a step of performing a first etching process to a material substrate having a laminate structure including a first conductive layer (11) and a second conductive layer (12) having a thickness of the thin wall portions (T1-T3), where the etching is performed from the side of the first conductive layer (11) thereby forming in the second conductive layer (12) pre thin wall portions (T1′-T3′) which has a pair of side surfaces apart from each other in an in-plane direction of the second conductive layer (12) and contact the first conductive layer (11). The method also includes a step of performing a second etching process from the side of the first conductive layer (11) for removing part of the first conductive layer (11) contacting the pre thin wall portions (T1′-T3′) to form the thin wall portions.