The purpose of this paper is to clarify characteristics of the concept of "unconscious" in S. Freud's psychoanalysis of the first topography, and also to considerate preliminarily the relation between subject and consciousness and unconscious. First, this paper will investigate characteristics constituting the concept of unconscious. Second, I will examine metapsychological presentation, and reveal that Freud's concept of unconscious is constituted not by means of descriptive but based on dynamic, topographical and economic aspects. The contents of unconscious is not only energy of instincts as "force" but also a ramified network of ideas as "meaning", and the function of representative of instincts make possible to connect "force" and "mea...