The recombination of hydrogen and oxygen in technical gaseous waste of nuclear power plants in enlarged scale experiment has been studied on the basis of our previous work. The catalyst and its best operating conditions for recombination of hydrogen and oxygen determined in a small scale experiment were demonstrated and tested. The results show that the data obtained in an enlarged scale experiment agreed well with that of in a small scale test. The recombination rate of H@'2 and O@'2 was higher than 98.3% and 99.98%, respectively. After recombination, the residual concentrations of H@'2 and O@'2 in waste gas were O@'2@ 3 ppm, H@'2@ 400 ppm. The Pd-Al@'2O@'3 catalyst and operating conditions determined for gaseous waste processing of nuclear power plants were satisfactory.