Mussels belonging to phylum Mollusca serve as vital biological indicators for assessing the influence of environmental change on marine ecosystems due to their widespread distribution, sessile nature, and sensitivity to environmental fluctuations. Being filter feeders, mussels accumulate pollutants and reflect changes in water temperature, salinity, and pH, offering valuable insights into the health of aquatic ecosystems. The physiological and ecological responses of mussels to ocean acidification, rising sea temperatures, and altered food availability make them potential indicators of climate-induced stressors. This review highlights how these changes affect mussel growth, reproduction, and survival rates, making them a proxy for broader ecosystem changes. Furthermore, their calcified shells provide historical records of environmental conditions for paleo studies. The integration of mussel-based monitoring with advanced analytical techniques enables the identification of early warning signs of ecosystem degradation, guiding mitigation strategies and marine conservation efforts. By leveraging mussels as bioindicators, this research underscores their critical role in understanding and addressing the multifaceted impacts of climate change on marine biodiversity and ecosystem stability.