Abstract: Flux-cored arc welding of 2205 duplex stainless steel plate was performed. The effects of different heat inputs (8.32,11.02,14.04,17.39 kJ·cm^-1) on the microstructure, ferrite content, impact properties, microhardness and pitting resistance of the welded joint were studied. The results show that the welding seam, fusion zone and heat affected zone of 2205 duplex stainless steel joint were composed of austenite and ferrite, and the ferrite content gradually decreased with the heat input increasing. When the welding heat input was 14.04 kJ·cm^-1, the ferrite volume fraction of the joint basically met the requirement of 40%-60%. With the increase of welding heat input, the hardness of the joint weld and the heat affected zone decreased slightly, the impact absorption energy of the weld metal increased first and then decreased, and the pitting corrosion rate of the heat affected zone changed little, while that of the weld decreased first and then increased. When the heat input was 14.04 kJ·cm^-1, the resistance to pitting corrosion of 2205 duplex stainless steel was the best.