Solid-state defects, such as diamond NV-centers, SiC divacancies have been studied as single photon emitters, which are fundamental resources of quantum information technology. Together with these solid-state emitters, 2D materials such as transition metal dichalcogenides and hexagonal boron nitride (h-BN) have also attracted much recent attention as new candidate materials possessing single photon emitters. Among these, atomic defects in h-BN are expected to be particularly promising for 2D-based future quantum information applications owing to emerging single photon emitters operating at room temperature. However, to use h-BN for quantum applications, their emission energy needs to be controlled. Here, we show the Stark shift induced energy control of single photon emitters in h-BN by fabricating h-BN/graphene van der Waals heterostructures. Upon the application of a vertical electric field, we observed various types of Stark shifts including linear, quadratic and V-shaped from h-BN emitters. In particular, the frequently observed linear Stark shifts suggest the existence of the out-of-plane dipole in the defect’s crystal structure, which is supported by theoretical calculations. Also, we observed the discrete change of the emission intensities induced by an applied electric field. Altogether, our observation on the electrical tuning of h-BN single photon emitters shows the potential of 2D-based photonic quantum information applications.