As the population of consumers of outdoor wear expands, there is increasing interest among consumers in trendy lifestyle outdoor. Accordingly, it is essential to develop designs that are drawn from outdoor wear. This can be limited to traditional mountaineering suits, and designs developed from men’s outdoor zip-up T-shirts, which are highly utilized in everyday life, are very important. This study developed the design of a summer zip-up T-shirt for men with both functional and aesthetic qualities. Visual images of foreign brands and domestic outdoor-focused T-shirts from the spring/summer seasons of 2013-2019 were collected to analyze the following modeling elements: silhouettes, details, colors, materials, and prints. In addition, the design concept was derived by analyzing presentations from the global outdoor trade Fairs (2013-2019). To develop a sustainable eco-friendly outdoor summer T-shirt for men, the concept was derived according to three categories: eco-friendly, sportismexpressed active elements of sports, and an outro-concept of urban town wear as an outdoor lifestyle. Thus, a total of 12 styles of design were developed. High utilization of the outdoor wear T-shirts (which are also popular as lifestyle wear), is an important aspect of building a segmented lineup of the slow-growing outdoor wear market and supports expansion of the scope of theoretical research on outdoor wear design.