In this paper we report a new type sealed-off branchseleeted CO-CO2 compound laser operating at room temperature for the first time. Approximate two handred lasing lines were obtained in the region of 5.2-6.3μm and 9.2-10.8μm. the highest output power of the stronger lines was about 2.5W(CO) and 10 W(CO2). The influence of CO2 concentration in the gas mixture, discharge current and pressure on the power distribution of the lining speotram of CO and CO2 was investigated experimentally. The excitation processes for CO and CO2 molecules in the compound laser have been analyzed.