The recent fashion market failed to satisfy the needs of female customers in their 30s who are demanding a slim jacket that makes the wearer look young and slim. Accordingly, the slim-fit jackets of domestic brands targeting the women in their 30s were collected to conduct look and movement fitting evaluations based on the standard somatotype, and a slim-fit tailored jacket prototype was developed based on the present findings. This research aims to increase the satisfaction level of the slim-fit jacket customers reflecting a variety of somatotypes of women in their 30s. The research process was developing jacket patterns fully reflecting the properties in terms of extra space and design lines for different somatotypes of women in their 30s based on the jacket pattern formulated through the advanced research, and then suggesting pattern design methods for the different somatotypes. In this sense, this research attempted to identify the problems concerning the slim-fit tailored jacket fitting for different somatotypes of women in their 30s. The main aim was to suggest ways to improve the customers’ satisfaction level regarding the fit, and enable the manufacturers to produce a well-fitting jacket reflecting the peculiarities of each somatotype.