The present invention provides crystalline polymorphic forms of Fingolimod HCl (I) and processes for preparation thereof. The application provides processes for preparation of crystalline polymorphic forms-&alpha, &bgr and &mu substantially free from process related impurities. The crystalline polymorphic forms of Fingolimod HCl (I) obtained by the processes according to the present invention having an XRDP pattern as per FIGS. 1, 3 and 5, which are useful as active pharmaceutical ingredient in pharmaceutical compositions for the treatment or prevention of autoimmune related disorder including multiple sclerosis.