Provided are a nitrogen-doped graphene sheet and a method for preparation and use thereof; taking aqueous ammonia as a nitrogen source, graphite oxide is added to a solvent and ultrasonically dispersed; next, concentrated aqueous ammonia is added and reacted at 40-150°C for 3-24 hours; then, a hydrothermal reaction is carried out at 80-200°C for 1-12 hours; after washing and drying, a nitrogen-doped graphene sheet is obtained. Also provided is a nitrogen-doped graphene sheet obtained using the method, and a use of the nitrogen-doped graphene sheet.