Despite the successes achieved in contaminant treatments with microscale Fe/Cu bimetals, some important limitations, such as high Cu loading and easily shedding of the Cu layer, cannot be ignored. The purpose of this research is to get a new mFe/Cu bimetal preparation method by changing the Cu(II) existence state during the preparation process. The Cu layer was regularly distributed on the surface of microscale Fe with uniform nanograde-sized globular shape particles (mFe/nCu) in the presence of complexants, which facilitated catalytic sites and galvanic couple formation. Furthermore, the reactivity of the prepared mFe/nCu bimetal increased linearly with the complexation constants (lgk(MY)) of the different complexants. Particularly, k(obs) (0.090 min(-1)) obtained by mFe/nCu bimetallic particles after five cycles was higher than that of the fresh mFe/Cu (0.074 min(-1)) bimetallic particles prepared without a complexant. This work improves the preparation of Fe/Cu bimetal and provides a deep insight into the improvement reason of reactivity and operational life.