Monel 400 alloy is widely used in marine engineering due to its corrosion resistance. In this study, the tribo-
corrosion behavior of Monel 400 alloy has been investigated under cathodic and anodic polarization conditions. 
The results revealed that the material loss increased under both cathodic and anodic polarization, while the 
damage mechanism varied. Under cathodic polarization condition, the damage is caused by delamination of the 
worn surface and crack propagation in the subsurface, which gets more seriously at more negative polarization 
values.  Under  higher  anodic  polarization  values,  the  lubricating  performance  of  in-situ  generated  corrosion 
product was weakened. As the anodic polarization value increased, the diameter of corrosion products increased 
and got easier to be sheared-off during the sliding process.