A pen holding arm connected to an elevation drive apparatus of a pen head of an automatic lead feed apparatus holds a pen or a writing instrument. The automatic lead feed or supply apparatus has a lead reservoir at one side of an automatic drafting machine provided with the lead feed apparatus, a lead feed shutter drops the lead contained in the lead reservoir one by one. The shutter is controlled to open and shut by a driving force of the pen head. The driving force gives a rotary oscillation and vertical oscillations to the lead reservoir, so that the lead smoothly drops from the lead reservoir into the instrument situated just below the reservoir. The lead is led in depth into the writing instrument by vertical driving of the elevation drive apparatus.