PURPOSE: To provide a manufacturing method of stably manufacturing an actuator having very thin substrate at low cost.

CONSTITUTION: A structure manufactured by respective steps including the forming step of an aperture part 14 is provided with a semiconductor substrate 12 leaving a framed shape intact. At this time, a flexible thin film 16 extends over the whole surface of the semiconductor substrate 12 in such a way as to cover the aperture part 14 wherein an actuator 10 is constituted. This actuator 10 is composed of a flexible thin film 16, shape memory alloys 20 provided on the surface of the thin film 16 and electronic circuits 18 provided on the rear surface thereof as well as wirings 22 and electrothermal converters 26 provided inside the flexible thin film 16. This structure 10 is cut down out of the structure by properly cutting off this flexible thin film 16. Furthermore, this actuator 10 is electrically connected to outer elements by forming an aperture part in the flexible thin film 16 on the part of the electrode forming regions 24 in the end parts of the wirings 22.