Pollen analysis of two radiocarbon-dated cores provides a history of Wyrie Swamp and the surrounding vegetation, and the result compares with other palynological data from southeastern South Australia. Eucalypt (Eucalyptus) forest or woodland with a scrub understory was the major element before about 50,000 years BP, between ca. 40,000 and 30,000 BP, and after ca. 11,000 BP. More open woodland prevailed between ca. 50,000 and 40,000 BP, and between ca. 26,000 and 11,000 BP. Casuarina stricta, common on sand dunes, migrated to the area about 10,500 years ago and remained as a dominant species until the time of European settlement at about 1840 ad . Postglacial expansion of this species implies that the climate since 10,500 years ago has been warmer than in the preceding period. It probably was drier during the period from 50,000 to 10,500 BP than in the Holocene. The driest period was from 26,000 to 11,000 BP, perhaps corresponding to the time of the last glaciation in Australia. The site is archaeologically important, as a number of wood and stone artifacts that date between 10,200 and 8000 BP have been recovered from the swamp sediments.