<p>Natural capital refers to the reservoir of natural resource stocks that yield resource flows and essential services that are indispensable for sustaining livelihoods. Within this framework, natural capital encompasses an array of environmental assets, including land, soil, water bodies, forests, and fisheries. In the context of refugees, access to natural capital primarily revolves around their ability to utilize and depend on the environmental resources in the vicinity of their living arrangements. This study focuses on examining how natural capital influences the livelihood security of Sri Lankan Tamil refugees in the state of Tamil Nadu, India. One of the critical findings of this study is that Sri Lankan Tamil refugees often lack the legal rights to purchase land in the host country. However, in their pursuit of self-sufficiency and income generation, some refugees have resorted to engaging in agriculture by leasing land from local landowners. This highlights the resourcefulness and determination of the refugee population to secure their livelihoods despite legal constraints. Water bodies serve as a fundamental source of water for domestic purposes, including drinking, bathing, and providing water for livestock. The ability to access and utilize these water resources is a crucial determinant of their daily well-being and, by extension, their livelihood security. Furthermore, livestock, including cows, goats, and poultry, are considered integral parts of natural capital in the refugee context. These animals are valuable assets for generating income and ensuring a sustainable source of nutrition. However, the limited space within the camp presents a significant constraint to the development of livestock, hindering their full utilization as a livelihood resource. The impact of natural capital on the livelihood security of Sri Lankan Tamil refugees is characterized by several challenges and inadequacies. Notably, refugees face substantial difficulties during the rainy season with water stagnating around their living spaces and infiltrating their homes. These recurrent issues not only pose immediate threats to health and comfort but also negatively affect overall livelihood security. <i>Clinical Trial:</i> This article does not report on a clinical trial. Therefore, registration in a clinical trial registry is not applicable.</p>