Lattice, charge, orbital, and spin degrees of freedom in condensed matter determine the fundamental properties of materials.The control of these degrees of freedom makes up the cornerstone of current modern electronic devices. However, in the diligent pursuit of multifunctional electronics more sophisticated controls of these degrees of freedom in new functional materials are highly desired. The functionalities at the interfaces have been one of the foundations to build up current semiconductor industry. Novel phenomena at artifi cial heterointerfaces have been attracting extensive scientifi c attentions in both condensed matter physics and materials science. Recently, lots of studies have suggested that complex oxide interfaces provide a powerful route to manipulate these degrees of freedom and offer new possibilities for the next generation devices. The representative discovery of complex oxide interface is an observation of a 2DEG at the LaAlO 3 /SrTiO 3 (LAO/STO) heterointerface. In order to gain the control of the functionalities at the LAO/STO interface, electrical gating has been realized. Furthermore, nonvolatile control of the local conduction at this interface has been demonstrated recently. The electrical control by a ferroelectric layer and the existence of polar substance of adsorbates on top of the LAO/STO heterointerface suggested that the transport properties at the interface are extremely sensitive to the stimuli from environment. This provides an opportunity to extend the control concept, to gain distinctness and reversible capabilities for practical applications. In this study, a generic approach of controlling functionality at the complex oxide interface through visible light is proposed. Localized surface plasmon resonance (LSPR) is the collective electron oscillations, which is confined at the surface of metallic nanoparticles. The excitation of surface plasmon resonance by an incident light at the wavelength where resonance occurs can generate very strong light scattering, resulting in the intense surface plasmon absorption band and signifi cant local electromagnetic field.  By decorating gold nanoparticles (Au NPs) on the LAO/STO heterointerface, LSPR becomes a perfect candidate to realize our light stimuli concept at the interface due to the two important effects: (1) Electric fi eld near the surface of NPs is greatly enhanced. Although this enhancement falls off dramatically with distance, it still can reach the interface of LAO/STO. (2) It could be excited by visible light source, suggesting potential in practical applications. In this Communication, powered up by a simulation result of LSPR effect on the Au NPs/LAO/STO systems, we demonstrate to show the optical control of electrical properties at complex oxide interface.