Studies of paleo-shorelines provide an understanding and enable reconstruction of paleoenvironment and paleoclimate, which can in turn aid in the interpretation of historical human settlement patterning in a region. This project explores paleo-shoreline changes in the lower central plain of Thailand in Samut Songkhram and Samut Sakhon over the last 4000 years. The methodological approach was to apply integrated geophysical surveys (2D resistivity imaging and GPR) that can detect paleochannels beneath the ground surface and identify any variations in directionality, orientation and outflow patterns to the sea. Palaeochannel structure provides insights into fluctuations in land forms and aquatic environment, and changes between fresh water, brackish water, and a shallow sea. A geological study of sediments, collected from 20 wells, combined with C14 dating of specific deposits in the sequence was also undertaken to enable the possible identification and timing of intertidal deposits, basal intertidal deposits, channel deposits and shallow marine deposits that could correspond to variations in coastal depositional events. The results indicate that shallow marine deposits dating to 3780 to 3290 years BP are found underlying other sediments at current depths of 4-5 m below modern ground surface. The succeeding intertidal deposits sediments have ages varying from 1680 years BP to the present. The results of this study correspond to the assumption that this area was a shallow sea around 2000 years BP. This helps to explain, and for us to understand, the spatial and temporal distribution of human settlements in this region during part of the prehistoric and protohistoric periods. The results reflect the fluctuation in past sea level change in the lower central plain of Thailand, and illustrate the encroachment of shallow seas, before they eventually receded and arrived at the present level of the coastline.