Nowadays, global environment of water, soil, and atmospheric systems has continuously been deteriorating due to the incessant release of toxic chemicals from various constructed sources. The existence of heavy metal ions in the environment poses serious threats to human health and the ecosystem. Therefore, this review focuses on the advent of nanotechnology that has given immense opportunities for developing advanced nanomaterials with unique functionalities. This review reports on the development of sensing techniques based on nanomaterials including metal and metal oxide nanomaterials, quantum dots, carbon nanomaterials and polymer nanocomposites. Nanomaterials well possess excellent electrical, optical, thermal, catalytic properties and strong mechanical strength, which offer great opportunities to construct nanomaterials-based sensors or devices for environmental pollutants. The nanosorbents themselves should be nontoxic, the sorbents present relatively high sorption capacities and selectivity to the low concentration of pollutants. The adsorbed pollutants can be removed from the surface of the nanoadsorbent easily and sorbents infinitely recycled.