This application belongs to the field of pharmaceutical technology, and relates to the crystals of glycyrrhizic acid derivatives, their crystalline and pharmaceutical compositions, and medical use thereof, and, in particular, to the crystalline form A, crystalline form B, crystalline form C, crystalline form D, and crystalline form E of magnesium isoglycyrrhizinate, the method of preparing the crystals, the crystalline and pharmaceutical compositions containing the crystals, and medical use thereof. The crystalline forms prepared according to this application have overcome the defects of the compound of Formula I prepared according to the prior art, such as solid caking, difficult filtration, hard drying, and poor clarity. They are also suitable for industrial production, and capable of improving product safety.