gamma-Bi2MoO6 catalysts prepared by a co-precipitation method were calcined at various temperatures (425-675 degrees C), and were applied to the oxidative dehydrogenation of n-butene to 1,3-butadiene in a continuous flow fixed-bed reactor. Conversion of n-butene and yield for 1,3-butadiene were high at low calcination temperature (425-475 degrees C), but were decreased with increasing calcination temperature (525-675 degrees C). Temperature-programmed reoxidation (TPRO) measurements revealed that the catalytic performance of gamma-Bi2MoO6 was well correlated with the oxygen mobility of the catalyst. Yield for 1,3-butadiene was increased with increasing oxygen mobility of gamma-Bi2MoO6 catalyst. Among the catalysts tested, gamma-Bi2MoO6 catalyst calcined at 475 degrees C showed the best catalytic performance due to its facile oxygen mobility.