Abstract: In the welding process of ultra-thin metal plates, the control of welding residual stress and deformation has an important influence on the product quality. The residual stress and welding deformation of 316 stainless steel ultra-thin plate (thickness 70 μm) during pulse laser welding process were studied. The thermo-elastic-plastic finite element method and the semi-ellipsoid moving heat source model were used to simulate the temperature field and stress-strain field of the ultra-thin plate structure by considering the geometry and material nonlinear factors of the model. A pulsed laser welding experiment was carried out, the temperature was measured using an infrared thermometer, the welding distortion was measured by a laser displacement sensor, and the residual stress was measured by an X-ray diffraction stress tester. The results shown that the model prediction were consistent with the experimental measurements results.