Abstract:  The concentration tracking analysis and constant-current electrolysis curve were adopted to study the process of ferrate(VI) electrosynthesis and the behavior of anode passivation in concentrated NaOH solution by using iron-grid anode.The results showed that the anode passivation degree during electrolysis can be described quantitatively by using Fe(VI) apparent electrosynthesis rate，theory electrosynthesis rate and decomposition rate and the equation is given as：θ=1-r(FeO↑2-↓4)↓app-r(FeO↑2-↓4）↓d\〗/r(FeO↑2-↓4)；It was found that the iron anode passivation can be avoided obviously under some conditions so that the Fe(VI) current efficiency will be kept at comparatively high level for a long time.The condition was as follows：temperature 35 ℃，current density≤6.1 mA/cm，alkaline concentration≥14.5 mol/L.A solution of Na↓2FeO↓4 with the concentration over 0.78 mol/L could be electrosynthesized successfully under the above condition and the corresponding mean current efficiency was 47%.