Since at the regime of nanometer, the quantum confinement effects are observed and the wave nature of electrons is more dominant. Therefore, the classical approach of current formulation in mesoelectonics and nanoelectronics results in inaccuracy as it does not consider the quantum effect, which is only applicable for the bulk electronic device. For accurate modeling and simulation of nanoelectronics, device atomic-level quantum mechanical models are required. In this work, an ultra-thin (3 nm diameter) Silicon- channel Cylindrical Nanowire FET (CNWFET) is designed and simulated by invoking non-equilibrium green function (NEGF) formalism and self-consistent Schrodinger-Poisson’s equation model. Then impact variation of temperature, oxide thickness, and metal work function variation in the proposed NWFET is investigated to analyze the distinct performance parameters of the device e.g. threshold voltage (Vth) drain induced barrier lowering (DIBL), sub-threshold swing (SS), and ION/IOFF ratio. The designed device exhibits reliable results and shows a SS of 57.8 mV/decade and ION to IOFF ratio of order 109 at room temperature.