The diverse applications of nanotechnology in environmental monitoring, diagnostics, sensing, antimicrobial, drug delivery, etc. are well established. Among these, the discovery of the remarkable catalytic activity of nanomaterials has spurred significant interest in recent years owing to their numerous possible applications in the field of environmental analysis. Contemporary environmental analysis methods rely upon natural enzymatic methods. However, challenges with protein isolation and the complex nature of protein synthesis make this strategy non-viable. A recent discovery that nanomaterials may also show biomimetic enzyme-like activity (nanozymes) has therefore offered a promising avenue to overcome several challenges associated with natural enzymes. This is because such active and purified nanozymes can be prepared in large quantities in a rather facile and highly reproducible manner. Further, being inorganic nanomaterials, these nanozymes can be easily functionalised with a variety of molecular recognition elements (MREs) that make them an attractive tool for environmental analysis, biosensing and diagnostics applications, including pesticide sensing and detection of small contaminant molecules. In this chapter, we will share recent developments in the use of nanomaterials as artificial nanozymes for environmental monitoring.