This article presents a study on process characterization and optimization of the metal nanoparticle fabrication process known as the submerged arc spray nanoparticle synthesis system (SANSS) for obtaining desired geometric sphericity of nanoparticles. The geometric shape characteristics of nanoparticles pose significant impact on innovative product and process design. The sphericity and surface roughness of prepared TiO2 nanoparticles can vary widely and are influenced by the process parameters being employed in the SANSS. To improve this, an in-situ nanofluid sampling and measurement approach was developed to analyze the particle shape characteristics and characterize the nanoparticle synthesis process. The particle shape contours obtained from FE-SEM and TEM were employed to quantify the TiO2 nanoparticle sphericity and analyze the effect of process parameters on particle roundness. The optimized process parameters were identified using the Taguchi method. Our results proved that the average sphericity of TiO2 particles prepared using the optimized process parameters was effectively improved up to three folds.