The interfacial electronic properties of PbI2 and BN van der Waals (vdW) heterobilayer are explored by using density functional theory (DFT) method. An intrinsic type-II heterostructure with a wide bandgap is demonstrated. The spatial separation of the lowest energy electron-hole pairs can be actualised and make PbI2/BN heterostructure as a good candidate for applications in optoelectronics and solar cell. A simulation of E-field is actualized to modify its electronic properties. Band alignment converts from type-II to type-I heterostructure separated by a forward voltage with the value of about 0.07 V/angstrom. Three regions implying different E-field-sensitive properties are obtained from the variations of bandgap with E-field. The charge redistribution with an E-field is mainly on the surface of PbI2 and BN layers as well as the amount of electrons depends on the strength of E-field. In addition, the PbI2/BN heterobilayer exhibits more outstanding optical conductivity capability. Our results could bring forward a new perspective on sensor and shed light on the design of novel nano-and optoelectronics based on the PbI2/BN vdW heterostructure. (C) 2017 Elsevier B.V. All rights reserved.