The present invention relates to a material for hydrogen-storage constituted by Ti-Mn alloy system which has a high hydrogen-storage capacity, plateau hydrogen dissociation equilibrium pressure, hypostoichiometric composition and crystal structure of C14. Ti-Mn alloy system for hydrogen-storage of the invention which has a C14 crystal structure, is represented as: Ti.sub.u Zr.sub.v Mn.sub.w Cr.sub.x V.sub.y X.sub.z, wherein, X is at least one of element selected from the group consisting of Fe, Al and Ni; u, v, w, x, y and z are mole numbers of each components; 0.7<u<1.0; 0<v<0.3; 1.0.ltoreq.w.ltoreq.1.3; 0.1.ltoreq.x.ltoreq.0.4; 0<y<0.3; 0.ltoreq.z.ltoreq.0.2; 0.7<u+v<1.0; 1.4.ltoreq.w+x.ltoreq.1.7; and, 1.3.ltoreq.w+x+y+z<2.0.