Provided are four crystal forms, A, B, C and D, of demethyleneberberine hydrochloride, and a preparation method therefor, and further provided are X-ray powder diffraction characteristic absorption peaks, infrared absorption peaks and DSC spectra of the four crystal forms. The X-ray powder diffraction characteristic diffraction peaks of the crystal forms are at about 8.205°, 8.805°, 10.817°, 14.835°, 15.479°, 16.668°, 17.492°, 18.529°, 20.656°, 21.536°, 23.538°, 25.657°, 26.192°, and 28.808°. A preparation method for the four crystal forms of the demethyleneberberine hydrochloride is also involved. The preparation method has a simple process, a high yield and a low cost; and has a high product purity and a stable quality.