The present invention relates to crystalline forms A and B of Tigecyclinehydrochloride and to methods for thepreparation of the same. Furthermore the present invention relates to the useof crystalline forms A and B of Tigecycline hydrochlorideas intermediates for the formulation of an anti-infective medicament. Moreoverthe present invention relates to pharmaceuticalcompositions comprising crystalline form A of Tigecycline hydrochloride in aneffective amount and to the use of crystalline formA of Tigecycline hydrochloride as anti- infective medicament.