For outdoor multimedia device, electrowetting display (EWD) is one of the potential technologies. In this paper, we evaluated the single layer multi-color EW device by using various colored oils without adopting color filter. The oils were dosed into the pixel by using ink-jet printing (IJP) technique. For colored oils, in order to improve the color saturation of EWD panel, we used mixed solvent to increase the solubility of dyes. Then, by using UP technique, a single layer multi-color EW device was successfully fabricated and the optical property had been evaluated. Also, to improve the reliability of fluid motion, a simulation named FLUENT was first adopted to predict and realize the fluid behavior under different electric force.