Dehydrochlorination of 1,2-dichloroethane (1,2-DCE) into vinyl chloride (VC) was carried out over polyacrylonitrile-based active carbon fibers (PAN-ACFs). PAN-ACFs showed excellent catalytic activity, although the lifetime was not sufficiently long enough for practical application. X-ray photoelectron spectroscopy (XPS) revealed that the active site was pyridinic nitrogen and that chlorine stayed on the surface after the reaction. Coke was also produced in the pores, as suggested by the weight increase. The heat-treatment after the reaction released hydrogen chloride from the ACF but no catalytic activity was restored. The preheat-treatment was found to shorten the catalytic lifetime. An optimum temperature and uniform distribution in the catalyst bed achieved by this fluidized bed may provide a practical process of sufficient life.