The microstructure and electrochemical properties of the Al-1Mg-0.1Sn-0.1Ga-xBi alloys were investigated by means of SEM/EDAX and electrochemical measurements, the self-corrosion was tested by using the gas-collecting method. The results show that element Bi in alloys is mainly segregated along the grain boundaries. The addition of Bi increases segregative phases which further activate the alloys to get more negative open circuit potentials, at the same time self-corrosion increases. Al-1Mg-0.1Sn-0.1Ga-0.1Bi has good comprehensive electrochemical properties, with ocp-1.693V (vs Hg/HgO) and self-corrosion rate 0.231 ml·cm-2 ·min-1 in 4 mol NaOH solution.