There is provided a micro power generator enhanced in efficiency and power generation output, and having an increased temperature range for operation. The micro power generator comprises: a high-temperature heat source; a low-temperature heat source; an enclosed body containing a working substance therein, the enclosed body being deformable by means of a phase change of the working substance between a first shape wherein heat can be transferred from the high-temperature heat source and a second shape wherein heat can be transferred to the low-temperature heat source; a permanent magnet constituting the enclosed body, the permanent magnet being maintained in a first position when the enclosed body has the first shape and in a second position when the enclosed body has the second shape; and a wire in which an electric current is induced by a movement of the permanent magnet. Further, the present invention provides an apparatus for producing a reciprocating movement between two heat sources having a temperature difference therebetween.