<p>The utilization of medical waste pyrolysis oil (MWPO) is crucial for resource recovery and environmental protection. This study investigates the physicochemical properties of MWPO, the effects of distillation temperature on its fractions, and the performance of ex-situ catalytic distillation for upgrading. The MWPO has a density of 0.98 g/cm³, a viscosity of 15.227 mm²/s at 40&#xa0;°C, and a heating value of 43.44 MJ/kg. GC/MS (gas chromatography/mass spectrometry) analysis showed that aromatic hydrocarbons were the predominant components of MWPO, accounting for 36.84% monocyclic aromatic hydrocarbons (MAHs) and 59.99% polycyclic aromatic hydrocarbons (PAHs). As the distillation temperature increases, the fractions exhibit higher density, viscosity, and aromaticity. The optimal conditions were identified as distillation at 200 °C followed by USY zeolite catalysis in ex-situ catalytic distillation. Under these conditions, the upgraded oil showed improved properties: density decreased to 0.79 g/cm³, viscosity reduced to 2.571 mm²/s, and heating value increased to 45.15 MJ/kg. Brunauer–Emmett–Teller (BET) and ammonia temperature programmed desorption (NH₃-TPD) characterizations indicate that the USY catalyst reduces PAH byproducts through micropore confinement and acid synergy, thereby enhancing MAH selectivity and improving oil quality. This study demonstrates a feasible catalytic distillation approach for MWPO upgrading and resource utilization.</p> Graphical abstract <p></p>