This chapter reviews the latest development of new nanomaterials-based biosensing platforms for environmental monitoring. In particular, we focus our attention in the analysis of different electrochemical analytical systems reported in the last 10 years. Various platforms will be described, pointing out their advantages and also the possible disadvantages. Biosensing platforms are becoming useful devices for environmental monitoring in particular for the use as screening tests for in situ measurement. Some of them are even being commercialized for detection of pollutants like the ones for the detection of heavy metals in different water samples. At the same time the recent years have shown development in the preparation, functionalization and characterisation of new nanomaterials. The new biosensing platforms made using these materials, given the improved analytical performance, could nowadays be an alternative to standard analytical instrumentation for in-field applications. For better understanding of these new electrochemical devices we discuss different nanomaterials (metal nanoparticles, carbon nanotubes, quantum dot and graphene) used not only for the modification of the electrode surface for enhancing the transfer of charge but also as carriers/supporting matrix of the biological recognition element (e.g., enzyme, antibody). The employed nanomaterials have clearly improved the effectiveness of the biosensing in addition of offering also new detection alternatives for various pollutants present in the environment.