Polypropylene (PP) is a polymer suitable for research of melt electrospinning. We examined the special properties of micrometer to nanometer order fibers produced through the latest heating-type melt electrospinning device whose amount of extrusion is strictly controlled. We found it necessary to control the extrusion speed of the six-nozzle type head to 0.4-0.6ml/h. This translates into a 1/10 or less decrease of speed in the melt electrospinning process while the extruding speed is 2.0-20ml/h in the melt blowing. When the melt temperature was lowered in melt electrospinning, the fiber diameter thinned. PP fiber spun from the nozzle by the electrospinning is believed to orient the molecular chains most effectively at the temperature of 250 ℃.