In this paper, since the heavy elastica theory is applicable in the analysis of silhouette of ladies' dress, the influence of bending length ³√ B/W (where B and W are bending rigidity and fabric weight per unit area respectively) on silhouette is studied. One-piece dresses are constructed of two kinds of fabric of women's thin dress, which have the ratio of ³√ B/W of 1 to 0. 74, and are made in two sizes of 1 to 0. 74 for each kind. Sensory test, optical and actual measurements and simulation test were under taken on these specimens and the results are summarized as follows : 1) Sensory test firstly resulted that the silhouette of one-piece dress which is made of fabric of larger value of ³√ B/W and of smaller size, appears harder, while that, which is made of fabric of smaller value of.³√ B/W and of larger size, looks softer. Secondly, the silhouette of one-piece dress which is made of larger value of ³√ B/W and of larger size looks the same as that which is made of smaller value of ³√ B/W and of smaller size. 2) It was found that silhouette of ladies' dress is closely related with both ³√ B/W and size, and that the result has good agreement to that of the sensory test. 3) In order to obtain the same silhouette of one-piece dress among different sizes, it is necessary to construct dresses in the same ratio of value of ³√ B/W as the ratio of size.