The apparatus for producing a nanofiber includes a supply unit (110) for supplying melted polymer for fiber material, a spinning unit (122) having several radiation nozzles (122) to which first voltage having a polar is applied to discharge the polymer solution supplied from the supply unit in a filament form, a collector (130) spaced apart form the spinning nozzles in order to pile the filament from the spinning unit and applied to second voltage having opposite polar to the first voltage, and a control unit (140) applied to the first voltage having the same polar as the charged filament and extended from an end of the spinning nozzle toward the collector at least at both sides of the spinning unit in order to prevent repulsion and dispersion of the filament stream radiated from each spinning nozzle.