Al and Al-Mn alloy were anodized in 1.0 M solution of sulphuric, oxalic, citric and tartaric acids with a variety of current densities (0.50-2.50 a.dm-2) It is found that, the inhibition pro- perty of the formed anodic filrns on both Al and Al—Mn increased with increasing the current density The effect of current density is greater in case of citric and tartaric acids. The effect of time was studied in 1.0 M acid solution at 1.0 a.dm“2 and time intervals 10-60 minutefu increasing the time accompanied with a decrease in reaction number. The results were treated applying both of Mylius equations and the mathematical treatment suggested earlier by us.