The purpose of this study was to examine the appropriate surplus of clothing for a suitable basic bodice pattern of Male Sports Athletes by using the 3D virtual twin and virtual garment simulation system. The results were as follows; 1. By using 3D virtual twin and garment simulation, new bodice pattern considered male sports athletes was development. The basic numerical formula were as follows ; surplus of chest girth=9, surplus of back length=1, armhole depth=back length/4+13, half back width=chest girth/5+2.5, front chest width=chest girth/5+3. 2. Wearing test by 3D virtual garment simulation system was useful to evaluate wearing outline, surplus of clothes and garment space. Also it estimated more highly than existing pattern in silhouette and ease amount, confirming that new bodice pattern is appropriate for the male sports athletes. New bodice pattern was evaluated to allow proper space length of chest and waist. Virtual models production through 3D body scan data, pattern draft and virtual garment digital program were applied to prototypic design method so as to enhance the fitness of ready-made garments. This study is expected to serve as one of important basic data for ensuing studies that may utilize 3D Virtual Garment Simulation System with 2D patterns, and also for future 3D Pattern Production Program development.