According to the characteristics of cast titanium alloy and welding assembly, the anodizing processes of cast titanium alloy weldments were optimized. On the basis of normal titanium alloy anodization, these process parameter such as anodization time, anodization solution temperature,anodization voltage and the acid corrosion time before anodization and so on for cast titanium alloy weldment were optimized. This conclusion shows that the optimized process conditions meet the demands of production quality.