Changes of farming system in the coastal areas of the Vietnamese Mekong Delta (VMD) have been happening as an inevitable trend under the context of climate change, especially salinity intrusion. However, these changes are sometime associated with very high risks or interest conflicts. Therefore, the local government has been attempting to control and manage these changes in order to lower the unexpected risks or conflicts for farmers in the coastal regions. However, the empirical evidences hidden behind changes of farming systems in the VMD were not fully recognized. The current study aimed at investigating the factors affecting the changes of farming system in Kien Giang and Soc Trang provinces by using binary logit model. The study found that the household head’ educational level was significantly and positively associated with the adoption of new farming systems. More importantly, the distance from fields to rivers or salinity level negatively affected the changes of farming systems. In case of change of farming system from sugarcane to mono–shrimp, the study also found that the number of female labor, accessing to credit, membership in organization and total agricultural land negatively affected the adoption of new farming system. In case of change of farming system from rice–shrimp to mono–shrimp, the study suggested that shrimp experience was positively associated with the adoption of new farming system.