This paper presents a livelihood vulnerability assessment and compares the levels of exposure, sensitivity and adaptation to climate change of the local populations in mountains area and coastal plains in Tunisian arid regions. The United Nations Intergovernmental Panel on Climate Change vulnerability index (LVI-IPCC) has been adapted and applied to assess this livelihood vulnerability, based on socio-economic surveys and semi-structured interviews with the local populations. Findings show that households in coastal plains are more vulnerable in terms of sociodemographic profile, food security, social networks, access to water and climate variability. This territory is much more exposed to climate change, despite being slightly less sensitive. On the other hand, households in mountainous territory are more vulnerable in terms of livelihood strategies, land tenure and health, despite their adaptation capacity, which reduces their vulnerability to climate change. Based on this vulnerability assessment, this work suggests specific adaptation strategies and measures for livelihoods sustainability in each territory.