The purpose of this study is to develop the well-fitted brassieres by observing the changes in the breast sizes and shapes, the surface area and the volume of the breast through the arm movements of 3 types (0$^{circ}$, 90$^{circ}$ and 180$^{circ}$) in vertical motion. The subjects are females, who are aged twenties and wearing a brassiere size 70B, In particular, to obtain the measures regarding the surface area and the volume of the breast, replicas are made at each motion. The results of this study are as follows: 1. The changes in the breast sizes and shapes at each motion By increasing the motions of the arm movement, the following measure items are inclined to decrease: Shoulder length, Side neck point~B.P., Front neck point~B.P., Horizontal length of the cup, Upper bust circumference, Bust circumference, Upper bust depth, Bust depth, Under bust depth, Nipple to tipple breadth, Horizontal distance of bust, Bust height, Cup size. By increasing the motions of the arm movement, the following measure items are inclined to increase: Center point of shoulder~B.P., Shoulder point~B.P., Armpit~ lowest point of breast drooping, Upper bust point~B.P., B.P~Under bust point, Under bust line, Width of gap between breast, Vertical distance of Bust. 2. The changes in the surface area and volume of breast at each motion By making the replica to observe changes in the surface area, which are sectioned to 4 parts(area 1 to area 4) , and volume of breast at each motion, the results are as follows: At 0$^{circ}$ and 90$^{circ}$, the sizes of each part are ordered as the following: area2> areal> area4> area3. At 180$^{circ}$, the sizes of each part are ordered as the following: areal> area2> area4> area3. Through these orders, it is found that the upper and inside part of the breast has the inclination to increase so long as the motions of the arm movement increase. Also, the total surface area increases so long as the motions of the arm movement increase. The volume of the breast increase when the surface area of the breast increases. As a result of the F-test on the changes in the each surface areas, the surface area and volume by arm movements, the significant differences among the each surface areas and the surface area are not found.