The present disclosure relates to novel crystalline forms of JAK inhibitors and the preparation method thereof. The novel crystalline forms in the present disclosure can be used for the treatment of autoimmune diseases, particularly for the treatment of rheumatoid arthritis. The novel crystalline forms in the present disclosure have good stability and remarkable purification effect in process, moreover, its solubility and hygroscopicity meet the requirements for medical use. The preparation method of novel crystalline forms is simple, low cost, and has an important value for future optimization and development of the drug.