1. A preparation method of D-glucosamine hydrochloride originated from plant is disclosed, which comprises using waste hypha residue of citric acid as initial raw material, acidolyzing the waste hypha residue with hydrochloric acid, condensing and crystallizing the acidolysis solution to produce crude product of D-glucosamine hydrochloride, decoloring the crude product with active carbon, condensing and crystallizing the decolored solution, centrifugally washing the crystal with organic solvent until it is white, and drying the crystal.