Sliding of highway embankments along riverbanks on soft ground has caused serious socio-economic loss annually in An Giang province, Vietnam. However, the nature of sliding problems has not been thoughtfully and systematically investigated. This study aims at better understanding of the factors causing the sliding and the mechanism of the sliding. Several analyses were conducted using the Slope/W 2007 software with the three selected site data: Binh My, Chau Doc, and Nhon Hoi which locate along the Hau river in An Giang province. The numerical results indicate that high fluctuation of groundwater and river water levels remarkably influence the stability of highway embankments along riverbanks. The sliding increases with increasing human activities along riverbanks. The toe of embankment slopes eroded in the dry season due to the lowest river water level triggers overall instability of embankments, and activates translational and rotational sliding. The climate change significantly increases sliding locations along the Hau river and Tien river, the branches of the Mekong river when it reaches the Vietnam-Cambodia border.