We report here a synthesis method for preparing single crystal Zn ferrite (ZnFe2O4) nanocubes with a high yield in aqueous solution. The morphology, structure and composition of the ZnFe2O4were investigated by SEM, TEM, XRD, XPS, FT-IR and ICP-AES. The as-prepared sample exhibits uniform cubic morphology. Moreover, the ZnFe2O4 nanocubes demonstrate drastically enhanced saturation magnetization valueMs. and the coercivity value Hc, compared to those of regular ZnFe2O4 nanocrystallines generated by conventional wet chemical processes. The synthetic strategy that introduces Fe ions into the tetrahedral A sites may be extended to prepare other ferrits. More importantly, the cationic substitution method reported in this work provides a new strategy to tailor the magnetic behavior of ternary magnetic nanocrystallines.