A novel hierarchical heterostructure of molybdenum dichalcogenide nanosheets homogeneously assembled on nitrogen doped graphene layer (MoS2 NSs/N-doped GR) was successfully developed by an easy and cost-effective strategy. The MoS2 NSs/N-doped GR was then utilized for accelerating hydrogen evolution reaction (HER) in alkaline medium. It was found that the nanohybrid exhibited highly efficient catalytic activity towards HER with higher current density and smaller overpotential as compared to those of other synthesized materials. In this context, the nanohybrid required an overpotential of only 208 mV to achieve a current density of 10 mA cm(-2), along with a small Tafel slope of 79 mV dec(-1), which is close to those of a commercial Pt/C. An outstanding stability of the nanohybrid for long-term operation was also demonstrated. The obtained results suggest that the MoS2 NSs/N-doped GR nanohybrid can be a potential candidate for HER in overall water splitting application.