Abstract: The metal type flux-cored wire for arc fusion 3D printing marine propeller bracket was developed by the alloying system design. The processing performance of the wire and the microstructure and mechanical properties of the deposited metal under the deposition current of 155-250 A and deposition voltage of 23-29 V were investigated. The flux cored wire was used to print the propeller bracket simulator, and the dimensional accuracy of the simulator was analyzed. The results show that the forming properties of the flux-cored wire was good, and the arc was stable. The spatter rate was less than 2.5%. The microstructure of the deposited metal was composed of pearlite, granular ferrite and lath bainite. The maximum width of bainite lath was about 0.80 μm, and there was high density dislocation and carbide in lath bainite. The yield strength of the deposited metal along the depositing direction was 550 MPa, and the tensile strength was 651 MPa; the impact absorbing energy at -20℃ was 58 J. The yield strength of the deposited metal in the vertical depositing direction was 538 MPa, and the tensile strength was 642 MPa; the impact absorbing energy at -20℃ was 60 J. Compared with ZG510 steel, the deposited metal had better strength-toughness properties. No cracks, pores and other defects were found in the propeller bracket simulator and the size deviation was within 1 mm.