The United Kingdom is home to a wide variety of ecosystems, from its ancient woodlands and heathlands to its coastal areas and wetlands. These habitats support a rich diversity of flora and fauna, many of which are native to the region and contribute to the ecological balance. However, two major threats to the UK’s biodiversity are pollution and invasive species. These factors have had a significant and often detrimental impact on native species and their habitats, disrupting natural ecosystems and posing challenges for conservation efforts. This essay explores how pollution and invasive species affect the flora and fauna of the UK, their consequences, and the measures being taken to mitigate these threats.