A combined molybdate-phytic acid passivation treatment on galvanised steel is studied in this paper. Both copper decoration drop tests and immersion mass loss tests indicated that the combined molybdate-phytic acid passivated samples showed better corrosion resistance than that of samples treated separately by molybdate or phytic acid. The electrochemical behaviours of the passivated samples were investigated using potentiodynamic polarisation and electrochemical impendence spectra in 0?5 mol L 21 NaCl solution and showed corrosion current densities of 4?95610 25 , 5?10610 25 and 1?19610 25 A cm 22 respectively. Electrochemical impendence spectra also indicated that molybdate-phytic passivated samples exhibited better corrosion resistance. The mechanism of synergetic effect for molybdate-phytic acid passivation on galvanised steel is discussed in brief.