Developing efficient and durable electrocatalysts for water splitting, which has long been regarded as one of the most promising patterns to produce green hydrogen, is of great significance but still challenging. Herein, ample Co/MoN heterogeneous domains/nitrogen-doped carbon (Co/MoN/NC) nanosheet arrays as high-performance hydrogen evolution reaction (HER) electrocatalyst via a typical nitriding-carbonization strategy are successfully prepared on nickel foam (NF), which exhibits a low overpotential of 29 mV at 10 mA cm^-2, together with excellent durability at 20 mA cm^-2 for 90 h in alkaline solution. Such excellent catalytic property for HER can be attributed to the generation of abundant Co/MoN heterogeneous structures. Additionally, the high conductivity of Co/MoN and NC also increases the charge transfer rate, further helping accelerate the reaction rate of HER. This work presents an efficient method for improving the catalytic hydrogen evolution activity in basic solution.