Abstract: The invention relates to a nanofiber web preparing apparatus and method via an electro-blown spinning. The nanofiber web preparing method comprises: feeding a polymer solution, which is dissolved into a given solvent, toward a spinning nozzle; discharging the polymer solution via the spinning nozzle, which is applied with a high voltage, while injecting compressed air via the lower end of the spinning nozzle; and collecting fiber spun in the form of a web on a grounded suction collector under the spinning nozzle, in which both of thermoplastic and thermosetting resins are applicable, solution doesn't need to be heated and insulation is readily realized.