Wire arc additive manufacturing (WAAM) has revolutionized various industrial sectors by offering a direct fabrication approach that reduces material wastage and deposition time. Surface finish and bead geometry are challenges in parts produced by the WAAM process, to control these limitations appropriate selection of process parameters is very important. This study focuses on optimizing deposition parameters such as travel speed, current, and gas flow rate for bead height and width of multilayered SS316L structures fabricated using a gas metal arc welding-based WAAM process. Optimization of process parameters is carried out using Taguchiʼs L9 orthogonal array and a linear/quadratic regression equation is developed for prediction of bead height and bead width. Additionally, analysis of variance (ANOVA) was used to assess the sufficiency and robustness of the developed regression equations. Values of R2 and adj. R2 was discovered to be close to unity for both bead width (BW) and bead height (BH) responses, demonstrating the model’s suitability. Main effect plots and analysis of variance (ANOVA) identify the most influential parameters and optimal parameter pairs. Results showed that travel speed has the maximum impact on bead height, followed by current and gas flow rate, and current exhibits the highest effect on bead width, followed by travel speed and gas flow rate.