Abstract-Polystyrene plastic samples containing brominated flame-retardants (BR-PS) were pyrolyzed at 400 C using hydrotalcite to reduce the content of bromine compounds in the oil produced, in comparison with using sand, zeolite-4A, and zeolite-13X. The bromine plastic sample was prepared by mixing tetrabromobisphenol A and polystyrene, and added to a glass reactor, together with hydrotalcite, sand, zeolite-4A, or zeolite-13X. The product oil obtained by pyrolysis at 400 C from the BR-PS was mainly composed of aromatic compounds, such as benzene, heptane, and toluene, and two bromine compounds, 2-methyl-2-bromopentane and 3-bromopropane. The product oil obtained using hydrotalcite contained aromatic compounds with low molecular weight, and bromine compounds were not detected. In comparison with the use of sea sand and molecular sieves, the amount of bromine compounds in residue decreased in the order of hydrotalcite > molecular sieves 13X > molecular sieves 4A > sand. Hydrotalcite thus trapped bromine in residue during the pyrolysis of BR-PS.