In this work, we present a three-dimensional dissipative particle dynamics simulation, which is independent of the initial conditions, for analyzing the wettability on liquid-solid interfaces. The model parameters are constructed based on simulation optimization. The contact angle of a droplet on the solid platforms which possess different surface energy is simulated. The normalized factors indicate the parameters of the surface energy. By tuning the attractive and repulsive effects between the platform and the droplet, the contact angles with wide range are found at steady states. In simulation result, the linear relation between contact angle and the normalized factor is obtained. The proper repulsive factor in the paper is recommended to be 15 or 20. The ranges of the contact angles are from about 65 to 155 degrees. Moreover, the local density and the equation of state are applied for determining the droplet’s self energy and compressibility. The simulation results will help us to predict the profile and internal physical behavior of a micro-droplet.