For laser splicing welding of stainless steel with thickness of 1.0 mm, the influence of clearance on weld strength was analyzed. When the assembly gap was 0 mm, orthogonal experiments was conducted on laser power, welding speed and defocusing amount to obtain the maximum tensile strength of welded joint and the corresponding optimal process parameters. The tensile strength of the weld was tested by welding experiments under different clearance conditions. The tensile strength of welded joints almost remained unchanged when the assembly gap was between 0 mm and 0.09 mm, but decreased sharply when the gap was 0.12 mm. When the assembly clearance was less than 0.09 mm, the microstructure of the fracture surface was rough and showed shear lip, and when the assembly gap was 0.12 mm, the weld was brittle fracture.