The invention relates to a konjac glucomannan pencil and a preparation method thereof. The preparation method of the konjac glucomannan pencil comprises manufacturing of a pencil plate, selection of alead, machining of a pencil rod and appearance decoration machining. Konjac glucomannan is used as a carrier and assists other auxiliaries, so that excellent bacteria resistance, high stretching strength and excellent flexibility are achieved; the konjac glucomannan is used as a pencil rod base material to achieve high tensile strength, high bacteria resistance and fall resistance compared with awood material; complete biodegradation, environmental protection, low carbon, convenient material taking and low cost are achieved; and the preparation process is simple. Compared with a traditionalpencil, the konjac glucomannan pencil achieves excellent performances, such as bacteria resistance, wet resistance and biodegradation, and can replace all pencils on the market.