In rural Vietnam, agriculture is the main source of food and livelihood for many households, making it a central component of programs to reduce poverty and achieve food security. As the sector faces multiple shocks from natural disasters, rural households are forced to develop strategies through diversification to cope with the increasing vulnerability associated with an increase in agricultural production. The study uses data from 344 households from the 2018 Residential Living Standards Survey (VHLSS) dataset. The results of the logit model indicate that the factors of labor force, mean age of labor, education level of labor, participation in party local mass organizations, households' access to credit, and saltwater intrusion have significantly influenced livelihood diversification. In addition, the multinomial logit model also found 13/16 factors included in the model that affect strategies for diversification of livelihoods from agriculture - wage employment, agriculture - nonagriculture, and a strategy that combines all three livelihoods above. In particular, saltwater intrusion has a negative impact on the ability of rural households to diversify. In addition, the study also found an inverse relationship between diversification and poverty. The propensity score matching results show that household participation in livelihood diversification has an impact on increasing household income. This reinforces the hypothesis that diversification contributes to poverty reduction in rural areas of the Mekong Delta. Therefore, in order to secure the capacity of rural households to practice farming along with a variety of income-generating activities to improve the welfare of the rural poor and have a significant impact on poverty reduction, participation in livelihood diversification should be emphasized in development plans.