Crystal form of compound, and preparation method therefor and use thereof

The present invention discloses a crystal form A of a compound, where the compound is S-(−)-2,3-methylenedioxy-5,8,13,13a-tetrahydro-10,11-dimethoxy-6H-dibenzo[a, g]quinolizine, and an X-ray powder diffraction pattern of the crystal form A includes three or more 2θ values selected from the group consisting of: 12.21±0.2°, 13.381±0.2°, 15.181±0.2°, 16.171±0.2°, 17.101±0.2°, 19.801±0.2°, 21.511±0.2°, 24.391±0.2°, and 25.321±0.2°. The crystal form A of the compound of the present invention does not contain water and a solvent, has high stability and low hygroscopicity, and is suitable for patent medicine.