a drilling apparatus , in which a hole and an insertion hole for a drilling rod are formed at a drilling position of a table and at a sheet pressing member capable of approaching or leaving a surface of the table , respectively , the drilling rod made of metal , capable of rotating at high speeds and reciprocating vertically are inserted through the both holes , the drilling rod has smooth peripheral and front end faces composed of at least part of a circular section having no blade , and a predetermined clearance is provided between the diameters of the hole and the insertion hole and the diameter of the drilling rod , whereby by pressing the drilling rod rotating at high speeds to the sheet , a sheet material is melted by frictional heat so that a beautiful hole is formed .