Abstract: Heat-resistant austenitic stainless steel is an ideal material for pressure vessels used in titanium sponge production, where the high-temperature properties and microstructure of welding joints significantly impact dimensional stability and service safety. Gas Tungsten Arc Welding (GTAW) and Shielded Metal Arc Welding (SMAW) was adopted to obtain the joint of a novel 06Cr21Ni19Si2N austenitic stainless steel. The microstructure and mechanical properties of the joint were characterized and tested by optical microscopy, scanning electron microscopy, XRD characterization, tensile testing and hardness measurements. The results show that the 06Cr21Ni19Si2N heat-resistant austenitic stainless steel welding joint is well formed. The weld metal solidified in an austenite-ferrite pattern. The weld metal microstructure consists of austenite with a minor amount of delta ferrite. Delta ferrite was also observed in heat-affected areas (HAZ) stainless steels. The HAZ is mainly composed of austenite and a small amount of delta ferrite, and grain coarsening occurs. At room temperature, the welded joint exhibits the average tensile strength of 738 MPa. At 1050°C, the average tensile strength of the joint is 85 MPa, the average yield strength is 59MPa. Microhardness testing indicates no softened or hardened zones within the welded joint, the peak hardness of the joint is 244 HV in the weld metal zone.