This paper presents improved performance of Double Gate Graphene Nanomesh Field Effect Transistor (DG-GNMFET) with h-BN as substrate and gate oxide material. The DC characteristics of 0.95[Formula: see text][Formula: see text]m and 5[Formula: see text]nm channel length devices are studied for SiO2 and h-BN substrate and oxide material. For analyzing the ballistic behavior of electron for 5[Formula: see text]nm channel length, von Neumann boundary condition is considered near source and drain contact region. The simulated results show improved saturation current for h-BN encapsulated structure with two times higher on current value (0.375 for SiO2 and 0.621 for h-BN) as compared to SiO2 encapsulated structure. The obtained result shows h-BN to be a better substrate and oxide material for graphene electronics with improved device characteristics.