Highly efficient with excellent stability electron field emitters based on monolayer graphene coated on well-aligned Si tip (graphene/SiT) arrays fabricated by a simple transfer method are demonstrated. The graphene monolayer is coated on the Si tip array using a chemical vapor deposition process, while the SiTs are prepared through the etching process of a Si substrate. The novel heterostructure field emitter enhanced electron tunneling, as a result, exhibits a better emission property. In addition, the fabricated microplasma devices based on the graphene/SiT heterostructure are closely correlated to the field emission properties of the graphene/SiT materials. The monolayer graphene supported on vertical SiTs provides the protruded nanostructure, which locally enhances the electric field and thus improves the field emission and the plasma illumination characteristics.