316L stainless steels with heterogeneous lamella structures were prepared by cold rolling and subse- quent annealing treatment. Then cold rolled steel plates were single and double welded by using GTAW welding process. Finally, microstructure and mechanical properties of rolled specimens and the welded joints were inves- tigated. The research results show that ultra-fined grains lamella structures are formed in the 316L stainless steels treated by cold rolling. The rolled samples exhibit a high tensile strength of 1058.9 MPa, an increase of 70.6% than that of original base metal samples. But the ductility reduces significantly, with a lower fracture e- longation of 16.9%. Weld microstructure of welded joints are typical equiaxial dendritic austenite, and a small amount of δ-ferrite. Coarse austenite grains are formed in the heat affected zone. Tensile strength of single-side welded joints is 608.1 MPa, and the elongation reaches to 15.3%, while mechanical properties of double-side welded joints appear a slight reduction. Equiaxed dimples morphologies are observed on all the fracture surfaces.