12Cr2Mo1R heat-resistant steel and 06Cr18Ni11Ti austenitic stainless steel are joined by Arc assisted activating TIG welding (AA-TIG) after using ERNiCr-3 and ER309 L filler metals pre-edge surfacing on the side of 12Cr2Mo1R. Scanning electron microscope (SEM) and optical microscope (OM) are used to study the microstructure of the joints. Microhardness, tensile strength and impact toughness are adopted to characterize the mechanical performances of the joints. Using CHI600D electrochemical workstation, and the potentiodynamic polarization and electrochemical impedance are employed to evaluate the corrosion resistance of the weld joints. The results show that the weld joints are formed well after pre-edge surfacing welding on the side of 12Cr2Mo1R base material. The microstructure of the weld by ERNiCr-3 and ER309 L welding wires pre-edge surfacing transition layer are single-phase austenite, austenite, and ferrite, respectively. The weld joint has excellent mechanical performances and corrosion resistance with the ER309 L welding wire pre-edge surfacing transition layer in the welding state. © 2020 The Society of Manufacturing Engineers