Flue-gas recycling combustion of coal was experimentally simulated by burning chars as well as their parent coals at 1120K in a miniature fluidized bed into which O_2/CO_2 or O_2/CO_2/H_2O mixed gases were fed. The fuel-N conversions into NO_x and N_2O both depended on the gas composition at the reactor inlet and the dependency was found to be due to that of the conversions of char nitrogen into the oxides. Characteristics of in-bed reduction of NO added at the inlet revealed that burning char and volatiles equivalently contributed to the reduction.