The Caspian Sea, the world's largest enclosed water body, experiences significant transformations in its physico-chemical properties and a decline in bioresources due to extensive anthropogenic activities. These activities include the discharge of diverse pollutants and bio-physical alterations such as over-fishing, hunting, and physical alterations to rivers. While acute manifestations such as a fall in the Caspian water levels and wetland desiccation are more overt, the pervasive impact of human activities contributes to a likely irreversible decline in environmental quality that we aim to spotlight in this discussion in order to facilitate its restoration. •Main challenges of the Caspian Sea (physical alteration, pollution and climate change) are introduced.•Long-term impact of the human intervention led to the decline of bioresources.•A systematic approach to the Caspian environment is required to highlight the key factors for restoration