Provided herein are solid state forms of Ruxolitinib besylate, processes for preparing the solid state forms, as well as pharmaceutical compositions and formulations comprising said solid state forms.Linvention concerne de formes solides de besylate de ruxolitinib, des procédés de préparation de ces formes solides, ainsi que des compositions pharmaceutiques et des préparations comprenant lesdites formes solides.