Single electron transistor (SET) is a key element in current research area of nanoelectronics and nanotechnology which can offer nano-feature size, low power consumption and high operating speed. SET is a new nanoscale switching device. It can control the motion of the single electron. The goal of this paper is to discuss about some physical properties of the SET and focuses on simulation of basic quantum device characteristics such as tunneling effect, Coulomb blockage, Quantum dot, Coulomb staircase, and Coulomb oscillation. The current-voltage characteristics of SET are explored for illustration. Two types of metallic and semiconducting SETs have been simulated.