Ordered mesoporous alumina (OMA) has been widely used as the adsorbents and catalyst supports due to their unique properties including highly uniform channels and large specific surface area. However, the thermal stability is not ideal enough. In this work, P-doped γ-Al2O3, which still maintained ordered mesoporous structure even when calcined at 1000 °C, was successfully synthesized via a sol-gel procedure with acetic acid as interfacial protector. The influence of the addition of phosphorus on the physicochemical properties of OMA and the catalytic behavior of its supported Pd catalyst was investigated by combining several characterization methods with catalytic activity test. The results showed that the introduction of phosphorus resulted in enhanced thermal stability, improved surface acid-base performance and increased reducibility of the Pd-alumina catalysts, all of which contributed to the excellent catalytic performance in conversion of hydrocarbon (HC), CO, and NOx. The obtained P-doped OMA is anticipated to be explored in other high temperature reactions due to its unique thermal stability and acid-base performance. Display omitted •Phosphorus-doped ordered mesoporous alumina with high surface area was obtained.•Doping of P improves thermal stability and surface acid-base property of γ-Al2O3.•Pd/P-OMA-10 represents high catalytic performances for CO, NOx and HC elimination.