Growing the Heusler Ni-Mn-Sn unidirectional crystals is challenging. In the present work, a modified zone melting method has been developed on the basis of traditional optical floating zone furnace, and high quality Ni47Mn38Sn15 unidirectional crystal has been produced in 0.8 MPa high-pressure atmosphere. Experimental results showed that the unidirectional crystal was beta(110) preferentially oriented and chemical compositions distributed almost homogenously. The modified high-pressure optical zone melting technique opens interesting perspectives for fabrication of unidirectional materials containing high manganese. (C) 2014 Elsevier B.V. All rights reserved.