Abstract: Fork bottom high relates to the proportion coordination of lower-body’s length and pants styles are comfortable or not, etc. In this paper, the research object are young female, using non-contact 3D body scanner to measure a large number of data, then using excel and SPSS software to analysis the data. The summary is that the difference between fork bottom high and the high of waist tend to 26.64cm, the ratio between fork bottom high and height tends to 0.44. On the other hand , dividing the target into 4 classes by clustering analysis ,and when the height changes by 4.9cm for each class,the fork bottom high changes by about 3cm.

Key words: body measurenent , crotch height , young women , ratio