Nanoscale 2 dimensional (2D) heterostructures based on zigzag graphene nanoribbons (ZGNRs) anti-symmetrically decorated with boron nitride (BN), are proposed as resonant tunneling diodes (RTD). Boron nitride has been utilized to decorate two edges of zigzag graphene nanoribbons in order to create required bandgap difference for constructing double barrier quantum well heterostructure. Nonequilibrium Green's function (NEGF) method including tight-binding (TB) Hamiltonian is employed to obtain transmission versus energy (T-E) curves and current versus bias voltage (I-V) characteristics of proposed heterostructures. Effect of structural parameters on the I-V characteristic is investigated. Proposed RTDs clearly show negative differential resistance (NDR) behavior in their I-V characteristic. Moreover, it is shown that the NDR behavior of proposed heterostructures can be precisely tuned by modulating structural dimensions.