This article proposes a new needleless electrospinning apparatus applying the method of splashing polymer solution onto the surface of a metal roller spinneret. When a high voltage is applied, many spinning jets form on the free surface of polymer solutions. Multiple electrified jets undergo strong stretching and bending instability, solvent evaporates, and solidified nanofibers deposit on the collector, as in an ordinary single-needle electrospinning process. The production of nanofibers is enhanced by 24-45 times comparing with a single-needle system. And the productivity is easy to scale up. The effects of processing parameters, including solution concentration, applied voltage, distance between spinneret to collector, and rotational speed of the roller spinneret on the morphology of nanofibers are investigated in this article. POLYM. ENG. SCI., 50:2252-2257, 2010. (C) 2010 Society of Plastics Engineers