This study presented functional designs for development of functional compression wear for men in their forties based on body muscles as well as designed 2D patterns using 3D standard body form data of men in their forties. Patterns with an optimal stretch rate were proposed through a comfort evaluation. Different material was used for different areas such as the sports ability strengthening areas including body parts that often move for sports (such as the shoulders, abdomen and lower arm), areas that require ventilation for perspiration (such as the chest and back center, and armpits), and stable form areas (such as the chest, waist and elbows). The front and back surface areas of the developed pattern was an average 102.4% size compared to the body surface area. The results indicated that the 90% reduction pattern showed changes in pressure value according to area of movement, had the best breathability when worn, and had the best, most comfortable fit compared to the other subjects. The clothing pressure values of the pattern were around 22.1- 23.4mmHg for the arm area (which has a big movement range and has many muscles) and 10.4-11.8mmHg for chest and abdomen areas related to major organs and breathing, indicating appropriate clothing pressure. A compression wear top pattern with pressure appropriate to the target age range and excellent appropriateness for the body form will be developed for men in their forties. A study method will be proposed to develop design technology for ergonomic compression wear tops with excellent fit and comfort.