The goal of this research was to determine the fiber and web properties of melt-blown (MB) thermoplastic polyurethane (TPU) polymer as dependent on the MB processing conditions. The relationships between the MB fiber properties and the MB process conditions, such as the die-to-collector distance and the velocity of the MB TPU fiber in the spin line, were measured and estimated on the basis of the air velocity and air temperature, respectively. Consequently, this study provided fundamental guidelines of heat, air flow, and distance conditions of the MB process for the production of commercially acceptable MB TPU nonwovens. More specifically, the essential insight into the MB process was fundamentally valid for the MB TPU process; however, the inherent heat sensitivity of the TPU polymer brought more complexity at fiber and web formation than the conventional polyolefin MB process. (c) 2007 Wiley Periodicals, Inc.