Polymer dispersed liquid crystal (PDLC) films can be prepared by the thermal polymerization-induced phase separation method, but the curing time is more than 7 hours, which leads to high energy consumption. In this study, the effects of triethylamine as a catalyst on the curing process and the electro-optical properties of PDLC films have been studied. Furthermore, PDLC films are prepared with different amounts of triethylamine to investigate the best ratio of the catalyst. It was found that using triethylamine as the catalyst could shorten the curing time from 7 hours to 1 hour, and the film with 5 wt% of triethylamine has the best electro-optical properties, and is as good as one prepared by the traditional method. All in all, employing triethylamine as a catalyst has been proved to be an energy efficient way of making PDLC films.