This research explores the fatigue resistance and mechanical characteristics of laser-welded butt joints produced by wire arc additive manufacturing, using AISI 316L stainless steel. Two separate sets of welding parameters were used to carry out the laser welding experiments. Analysis of the joints’ microstructure was performed using electron backscattering diffraction (EBSD), while optical microscopy was utilized to examine weld morphologies. Hardness tests were performed to evaluate the mechanical characteristics of the heat-affected zone (HAZ). Moreover, tensile testing was performed to examine the mechanical properties of the joints, while bending fatigue tests were used to determine their fatigue strength. Microstructure analysis revealed that the HAZ was indiscernible, with microstructural changes observed solely in the weld metal. Hardness measurements indicated a slight increase in joint hardness compared to the base material. Welding parameters notably influenced weld morphology. The results of the tensile tests showed that the tensile strength of the laser-welded joints was comparable to that of the base material. However, fatigue tests revealed a significantly lower fatigue limit for the welded joints compared to the base material.