UV-curable films of polymer dispersed liquid crystal composed of nematic liquid crystal and methyl methacrylate prepolymer were prepared. A device was fabricated by sandwiching the cured 'liquid crystal/PMMA' composite films in between two conductive glasses. The device shows electro-optic response properties with an applied voltage. The threshold voltage of the device depends on the curing conditions, degree of polymerization of PMMA and components, etc. The characteristics of the device, including the optical transmittance, response time, and contrast, are highly influenced by following factors, such as component ratio, and monomers. The investigation of SEM photographs for the cured films show that there is a close relationship between the liquid crystal droplet size therein and the electro-optic behavior of devices. From experimental results, when the droplet size increases, the optical transmittance increases and driving voltage decreases. The threshold voltages are between 15 - 20 Vrms and the driving voltage at the clearest state is about 40 - 50 Vrms for the prepared device, meanwhile, the rise time and the fall time at the clearest state are about 30 and 50 ms, respectively, and the contrast ratio is over 12.