This study was to provide the fundamental data for a scientific and rational clothing construction by investigating the length variation of the upper arm surface, using the method of surgical tape, and to understand the expansion and contraction of parts of body for the making of clothing adaptable to movement. The subjects were li early elementary schoolgirls in Busan area classified with three somatotypes, and arm-movements consisted of 6 types. The statistical analyses used in this study were mean, standard deviation and the ANOVA and LSD procedure. The results of the analysis of the length of the upper arm surface are as follows: By arm-movements, in the items of horizontal, upper arm length changed more in the front than in the back, and in the items of vertical, represented the opposite of horizontal items. In the items of upper arm, the anterior-posterior axilla length and under arm length were influenced by arm-movements, and the under length of the upper arm represented the maximum rate increase of 74.59%(3.20cm)$sim$138.72%(4.28cm). In the somatotypes of early elementary schoolgirls, type II was more influenced by arm-movements, and for the making of clothing adaptable to movement, type III needed to reflect more surplus length(2cm) than the other types.