Qu hydrochloride polymorph he Willingen iii and iv Form and preparation method

The present invention discloses a drotaverine hydrochloride polymorph, Form III, respectively, Form IV, wherein the X-ray powder diffraction pattern of Form III expressed in a diffraction angle 2θ ± 0.2 ° at 3.985 °, 7.969 °, 8.959 °, 10.459 °, 15.965 °, 17.011 °, 22.181 °, 23.346 °, and 24.548 ° displays characteristic peaks; Form ⅳ at 4.164 °, 8.288 °, 8.939 °, 11.465 °, 15.866,16.596 °, 22.261 ° and display characteristic peaks at 24.076 °. The present invention also discloses a method for preparing the above crystalline form. The present invention disclosed crystalline III, Form IV direct type uses water as the crystallization solvent, good stability, simple preparation method.