As a typical representative of the third generation semiconductor materials, silicon carbide (SiC) is one of the most ideally wide band gap semiconductor materials, which has a wide application prospect in semiconductor lighting device and electronic equipment. In this work, we have systematically investigated structural and electronic properties of monolayer SiC on fully-hydrogenated BN nanosheets (SiC/HBNH) and studied the effects of electric field on the band gaps of SiC/HBNH heterobilayers using first-principles calculations based on the density functional theory with van der Waals corrections. The results show that the position of Si and C atoms relative to HBNH nanosheet can determine the structural stability and the interaction strength between SiC and HBNH nanosheets. Therefore, the stacking types can effectively regulate the energy gaps of SiC/HBNH heterobilayers. Moreover, the conduction band minimum and valence band maximum of the heterobilayers are determined by SiC and HBNH nanosheets, respectively, leading to the separation of electrons and holes. Applying an electric field, a linear distribution of band gaps is a function of the strength of electric field, accompanied with a transition from direct semiconductors to indirect semiconductors even to conductors, which are primarily induced the stronger interaction between SiC and HBNH nanosheets. The results demonstrate that the stacking arrangements and electric field can effectively tune the electronic properties of SiC/HBNH heterobilayers, and reduce the recombination probability of electrons and holes, which open a way for the diverse and tunable electronic properties of semiconductor heterostructures in novel electronic nanodevices. © 2022, Materials Review Magazine. All right reserved.