An automatic garment pattern generation system was developed for the application to a three dimensional apparel CAD system. The traditional garment production method depends mostly on the flat pattern process except for some bespoke garment. To make a garment, a skilled patterner gathers the anthropometric data from selected people and draws predefined basic patterns based on them. The drafted patterns are sewn into a garment preform to be tried on the human body and adjusted until satisfactory fitting is achieved, which may take considerable time because the evaluation of fitting tends to depend on subjective feelings. Such complicated processes require high skill and therefore raise the overall production cost, moreover, the lengthy development period can result in loss of the competitiveness of the manufacturer by dissatisfying the current needs of demand activated manufacturing. To make such processes more efficient, we used effective computer technologies. In this study, we developed an automatic pattern generation method using three dimensional measurements of the human body and a garment model. The shape of the garment model is adjusted to fit the body and subsequently flattened into two dimensional patterns considering the properties of the fabric to be used.