Miniaturized integrated optical devices with low power consumption have long been considered hot candidates for plasmonic applications. While 2D materials such as graphene have been proposed for this purpose, they suffer from large propagation loss and low controllability at room temperature. Here, a silicene-based optical MOSFET with excellent performance is designed to achieve integrated circuit optical technology. The designed device is comprised of a silicene optical waveguide whose switching operation is performed by a gate and has a structure similar to an enhancement MOSFET with a formed channel. Unlike graphene, the surface conductivity of silicene can be controlled by both chemical potential and an electric field perpendicular to its surface. This unique feature of silicene is used to design and simulate an optical-MOSFET with transverse electric polarization at 300 K. The salient characteristics of the optical device include its nanoscale dimensions, ultra-low insertion loss of 0.13 dB, infinite extinction ratio, and quality factor of 688, proposing it as a promising tool for optical integration.