an electrospinning apparatus capable of : forming a buffer section between the respective units of the electrospinning apparatus and installing a vertically movable adjustment roller in the buffer section to adjust the transfer speed and time of a long sheet , which passes through the respective units , for each section and prevents the crumpling , sagging , snapping , breakage , and damage of the elongated sheet , avoiding abnormal transfer of the elongated sheet due to electrostatic attraction during electrospinning and , in a nanofiber production step , disposing an apparatus for detecting the sagging of the elongated sheet before and after a spinning zone , detecting the sagging of the elongated sheet , and transmitting the signal to an apparatus for assisting the transfer of the elongated sheet so as to adjust the transfer speed of the elongated sheet . this automatically improves the sagging of the sheet and thereby effectively prevent the problem caused by the sagging of the sheet .