The mixture of SF6 O2 and He which are regulated is injected into a discharge tube with 8 high-voltage electrodes. The divided F is injected into throat along flow direction. H₂/D₂ is injected along a long normal to the flow at the top and the bottom of the channel. The optical axis is located at 1 mm downstream of H₂/D₂ injectors. A small-scale continuous-wave DF/HF chemical laser is investigated. Experimental measurements indicate that its multiline output power is related to the flux of SF6, He and H₂/D₂. The effect on output power and laser device of O2 addition is investigated. The maximum net outputs of HF and DF are 12 W and 11 W respertively. The power is stable and regulated continuously, and the maximum operation time is 20 min.