Purpose 3D garment design technology is developing rapidly thereby creating a need for different approaches to developing the patterns. The purpose of this paper is to evaluate the 3D dynamic ease distribution for a 3D garment design. Design/methodology/approach Standard garments were created from Size 2 to Size 14 for ten human subjects. Landmarks location on both human body and the standard garment under dynamic postures are recorded, and he fit and comfort evaluation of the standard garment were collected from the ten human subjects. Finally, these data were used to evaluate the 3D dynamic ease distribution for a 3D garment design. Findings 3D dynamic ease evaluation is challenging and the findings showed that the upper-arm design is a core element of the whole 3D garment design. The upper arm is not only a connecting part for both front and back pieces of the garment, but is also the main active part of the body, so it is the essential element to affect the comfort and fit of the garment under dynamic postures. Originality/value This research provides a novel 3D ease evaluation by analyzing the landmarks location of both human body and standard garment, and fit and comfort evaluation of the standard garment, which are all carried under dynamic postures.