In order to investigate whether Al-Ga alloys can be used as a galvanic anode for cathodic protection, discussion of anodic polarization curves and galvanic anode tests were conducted in a neutral solution containing NaCl and Na2SO4.The results obtained were as follows;(1) Pitting potential was observed on the anodic polarization curves of Al alloys in the solutions containing Cl-. The Al alloys were abruptly activated at a potential approximate to the above pitting potential and the increase of anode current was observed.(2) As for the effect of additional gallium on the pitting potential, the potential became less noble with the increase in the amount of additional gallium.(3) The pitting potential became nobler when the purity of Al in the alloy was higher.(4) The pitting potential became slightly nobler with the increase in the concentration of SO42-.(5) The uniform corrosion of Al-Ga binary alloys could not be obtained by the addition of gallium.(6) The results of galvanic anode tests revealed that the current efficiency tended to decrease with the increase in the amount of additional metal.(7) The spontaneous electrode potential of Al-Ga binary alloys became less noble with the increase in the amount of additional alloying element, gallium.