Abstract: Nuclear grade 316L austenitic stainless steel specimens were prepared by cold metal transition arc additive manufacturing, and the microstructure characteristics and intergranular corrosion resistance of different regions of the spicimens were analyzed.The results show that the structure of the weld bead and the heat affected zone is mainly composed of austenite and delta ferrite, and the both show the characteristics of columnar dendritic growth. The ferrite content of the weld bead and the heat affected zone is 16.1% and 12.8%, respectively, and the secondary dentrite content of the skeleton ferrite in heat affected zone is bigger than that of the weld bead.The structure characteristics of the bottom, middle and top of the specimens are different, and the primary dendrite arm spacing gradually increases along the stacking height direction.The test piece was tested for resistance to intergranular corrosion in accordance with the requirements of nuclear power design specifications, and there is no crack, and the resistance to intergranular corrosion meets the requirements.