"Fashion Drawing"is a general name of drawings that express the fashion. This paper describes a historical transition and principles of drawing methodology of costume design drawing as still life in fashion drawing for making costume. Furthermore, this paper proposes an original drawing system named "the drawing method for prototype of costume design in fashion drawing" similar to the drawing method for a plane figure of formative costume. In addition, this paper proposes the real proportion as the traceable and absolute origin, "the basic proportion for costume design drawing" and the prototype of costume design drawing." The proposed method is applicable to a series of the system from the basic costume pattern made by human body size to a plane figure of formative costume. The proposition of" the drawing method for prototype of costume design in fashion drawing" is significant in fashion design.