The corrosion behavior of AXJ530 magnesium alloy in 3.5% NaCl solution at 25°C and pH 7.25 has been studied. Die-cast and thixocast specimens were tested using constant immersion technique, potentiodynamic polarization measurements and electrochemical noise analysis. The microstructure of cast specimens and their surface aspect after corrosion tests were analysed and compared. The results show that thixocast specimens have the best corrosion resistance. Their superior corrosion resistance can be attributed mainly to the presence of large pre-existing α-Mg grains.