Laser powder bed fusion (LPBF) has emerged as a promising manufacturing process for Inconel 718 (IN718), enabling the fabrication of geometrically complex components with desirable microstructural control. Several interdependent phenomena, including laser-powder interaction, rapid solidification, and solid-state phase transformations, occur during LPBF processing and determine the microstructure and mechanical performance of the as-built material. In this work, the influence of process parameters on the density and surface roughness of LPBF IN718 is investigated through a design of experiment (DOE) with varying parameters — laser power (100–200 W), scan speed (900–1500 mm/s), and hatch distance (50–90 µm) —across 27 combinations. A volumetric energy density (VED) threshold of approximately 67 J/mm³ is identified, below which lack-of-fusion (LOF) defects dominate, and relative density falls below 96%.