Erosion of Tien and Bassac river banks in the Mekong River Delta becomes more and more serious, increasing in both frequency and scale. Research on the current status and change in their riverbed morphology contributes to identifying the causes and proposing the effective preventive measures. The high-resolution shallow seismic method was used to investigate the current status of two river sections of Tien river, (Chau Ma river island and Sa Dec city areas) and Vam Nao river, thereby assessing the change in riverbed morphology of the Tien river section in Sa Dec city area.