The production of green hydrogen through the splitting of water is an alternative and efficient approach for energy conversion, reducing dependence on non-renewable fossil fuels and mitigating climate change. However, the efficiency of green hydrogen, which is produced from water electrolysis, is completely reliant on the high-cost noble platinum group metal (PGM) catalyst. It is essential to find a suitable alternative for PGM catalysts for water splitting. Two-dimensional (2D) layered materials have been considered as potential alternative bifunctional electrocatalysts to PGM for hydrogen evolution reaction (HER) and Oxygen evolution reaction (OER)oxygen evolution reaction (OER) owing to their specific structural and chemical properties, and low cost. In this chapter, we discussed the catalytic activity of 2D layered materials, including transition metal dichalcogenides, layered double hydroxides, MXenes, graphene, and their derivatives. Furthermore, we focus on the recent development of 2D layered material catalysts for both HER and OER activity in the field of overall water splitting. Also, outline some advanced approaches for improving bifunctional activities, including hetero atom doping, defect engineering, composites, heterostructures, hybridization, and interface modulation. Finally, we are discussing some issues and challenges for making commercialization of the 2D layered materials that remain in this rapidly growing field. We assume that the comprehensive and systematic content will increase reader engagement and encourage further research interest.