Catalytic combustion,which achieved the combustion of lean-natural gas/air mixture below the flammability limit of conventional combustion and improved the ratio of energy utilization with 100% fuel efficiency.To improve the catalytic combustion thermal efficiency,on the basis of catalytic combustion burner Ⅱ,the catalytic combustion burner Ⅳ was designed.Moreover,the combustion conditions of catalytic combustion and gas phase combustion in burner IV were analyzed respectively,and the thermal efficiency of catalytic combustion was compared with gas phase combustion.Experimental result shows that under other similar conditions,catalytic combustion has higher thermal efficiency than that of gas phase combustion when excess air ratios of catalytic combustion was higher.