The invention relates to crystalline forms of zotepine hydrochloride, including the crystalline hydrochloride salt of zotepine and two cocrystals of zotepine hydrochloride with benzoic acid. The preparation and characterization of these crystalline forms of zotepine hydrochloride is described. The invention also relates to the therapeutic use of the crystalline forms of zotepine hydrochloride to treat central nervous system disorders and to pharmaceutical compositions containing them.