Plasmon photochemistry can potentially play a significant role in photocatalysis. To realize this potential, it is critical to enhance the plasmon excited hot carrier transfer and collection. We apply the non-adiabatic molecular dynamics (NAMD) simulation to study hot carrier dynamics in the system of Au nanocluster on top of GaN surface. By setting up the initial excited hole in Au, the carrier transfer from Au to GaN is found to be on a sub-pico second time scale. By applying different external potentials to mimic the Schottky-barrier band bending, the charge transfer efficiency can be enhanced, demonstrating the importance of the internal electric field. Finally, with the understanding of the carrier transfer’s pathway, we suggest that a ZnO layer between GaN and Au can effectively block the “cold” carrier from returning back to Au but still allow the hot carrier to transfer from Au to GaN.