Summary pollen diagrams and carbonized particle concentration figures from cores collected very near the central Thai archeological site of Khok Phanom Di (ca. 4000-1000 BC) located ca. 0.22 km from the Gulf of Siam and 50 km from Bangkok are presented. These pollen analyses are the first associated with an archaeological site in Thailand and reveal a change from probable shallow water marine conditions through an apparent freshwater/dryland forest phase dominated by grass pollen. Grass pollen increases first in a core nearest the site and is associated with peaks representing charcoal concentrations. Burning of mangrove vegetation by man, as sea level fell, appears plausible. Earlier charcoal peaks may relate to the first occupation and subsequent, very localized vegetation disturbances. Ten samples from two cores are currently being dated at Oxford using accelerator mass spectrometry. Unfortunately results are not yet available.