The atoms site preference in the Al(3)Ti-Zn system has been studied using H. Rietveld method. The Ll(2) Ti(Al, Zn)(3) particles evolve in a ZnAl25 melt from the Ll(2) TiZn(3) particles in the ZnTi4 master alloy. It is found that Zn is replaced by Al during the transformation TiZn(3) -> Ti(Al, Zn)(3). In the evolving fee Ll(2) Ti(Al, Zn)(3) phase Ti occupies (0, 0, 0) position while Al and Zn occupy (0, 0.5, 0.5) position, similarly to Al and X in the Al(3)Ti-X systems, where X = Ni, Cr, Mn, Cu, Ag, Pd [1, 2].