Despite extensive hydrocarbon production from the Gippsland Basin, limited integrated 3D modeling studies have comparatively assessed the structural, geochemical, and petrophysical variations between the Kingfish and Volador formations across oil- and gas-producing fields. This gap hampers accurate reservoir characterization and development strategies. To address this, a comparative 3D modeling analysis was conducted on the Kingfish and Volador formations in the Kingfish Oil and Kipper Gas fields, Gippsland Basin, Australia. Structural analysis revealed NW-SE trending steep faults (70–72°) in the Kingfish Field and shallower WNW-ESE faults (62.5–65°) in the Kipper Field. Facies models indicated similar stratigraphic successions, with upper high-energy sandstones transitioning to organic-rich shales at the base. Geochemical analysis showed the Kingfish Formation has TOC of 1.0–12.0 wt%, HI of 120–140 mg HC/g TOC, and higher maturity (Tmax 422–430 °C; % VR 0.50–0.52 %), consistent with deeper burial. In contrast, the Volador Formation has TOC of 2.0–6.0 wt%, higher HI (150–210 mg HC/g TOC), but lower maturity (Tmax 422.5–428 °C; % VR 0.48–0.49 %). Petrophysical results showed superior reservoir quality in the Volador Formation, with porosity of 10–25 %, permeability up to 10 mD, low clay volume (0–25 %), and water saturation of 50–100 %. The Kingfish Formation displayed more variable porosity (2.5–22.5 %), lower permeability (<10 mD), higher clay content (2.5–55 %), and water saturation of 40–95 %. Limited data from deeper Kingfish sections highlight the need for further exploration