Metroxylon paulcoxii is a species of palm endemic to the Independent State of Samoa, formerly called Western Samoa. It is reported there from the islands of 'Upolu and Savai'i. The species is named in honor of ethnobotanist Paul Alan Cox. The species is similar to M. warburgii (also present in Samoa), but with shorter leaflets and with second-order branching in the inflorescence instead of third-order.