As time goes by and shape of body shape change, clothing sizes of national standard GB1335-1997 don't quite match Fig., and low coverage rate of size series becomes obvious situation, especially in recommended size configuration area. So there is an urgent need to study on configuration of human body and garment match, and then rationality of current size configuration was perfected. In view of national size configuration, shirt armhole was used as a sample; two sets of data were built and studied in recommended and non-recommended configuration area. The correlation and stability of chest girth change and D-value which obtained from armhole length and arm root girth were analyzed in detail. The possibility and feasibility of match between size configuration and body shape were shown. New way of analysis was explored by experiments, which could be used for reference in further research of size series.