Purpose. Saltwater intrusion affected seriously the livelihood of mangosteen growers in Ben Tre, a coastal province in the Vietnamese Mekong Delta in 2016. This study assesses how saltwater intrusion influenced the livelihood vulnerability of the mangosteen households and communities. Methodology / approach. This study used the United Nations’ Livelihood Vulnerability Index (LVI) and a similar index from the Intergovernmental Panel on Climate Change (LVI-IPCC) using data from 196 interviewed mangosteen growers in Cho Lach district, Ben Tre province in 2016 and 2018. A total of twenty-five (25) indicators are applied to calculate the two indices, using data as exposure to saltwater intrusion and natural hazards (5), socio-demographic factors (11), and sensitivity of health, finance, and source of water for domestic use (9). Results. The analysis results show that mangosteen-growing households had a medium vulnerability in 2016 and 2018 based on both indices. However, they were extremely vulnerable due to saltwater intrusion in 2016, and a high household percentage had a moderate value in the vulnerability index. They did not experience how to respond to saltwater intrusion and received a late warning on saltwater intrusion from the local authorities and media. However, mangosteen-growing households had a quick adaptive behavior to shift to new crops to improve their income in 2018. Originality / scientific novelty. The study provides a set of indicators to assess the vulnerability of this low-vulnerable area based on past studies as well as the actual situation of the study area in 2016 and 2018 to determine what factors influenced the main components, LVI and LVI – IPCC. These indicators represented the characteristics of the rural households in Vietnam and other Asian countries. This research also indicated how LVI and LVI – IPCC results differently and when they should be used. The analysis identified the factors influencing the LVI and LVI – IPCC by levels of saltwater intrusion in different years of 2016 and 2018, two different severe and less severe sites, adaptive and non-adaptive households, and their interaction. Practical value / implications. LVI and LVI-IPCC are good indicators for local and regional assessments on how saltwater intrusion and natural hazards affect households’ and communities’ livelihood and thereby how to guide them to respond promptly in such cases.