To overcome their respective drawbacks in fire suppression, 2-bromo-3,3,3-trifluoropropene (BTP) was combined with water mist to be a new binary agent. Then its performance in suppressing wood crib fires was experimentally evaluated in a confined space, in terms of fire extinguishment time and HF concentration. In the binary agents, the volume fraction of BTP (omega) was varied from 10% to 80%. For comparison, fire suppression tests with pure water mist and BTP were also conducted. Results showed that the volume fraction of BTP in the binary agent had a significant influence on its suppression performance. With ! increasing, both the fire extinguishment time and HF concentration decreased first and then increased, showing a "V"-shaped changing trend. At omega = 50%, the best performance was achieved, with the fire extinguishment time reduced by more than 2 times as compared with that of neat water mist and HF concentration reduced by 62% as compared with that of neat BTP. It was revealed that simultaneous application of BTP and water mist was an effective means of fire suppression, which could be ascribed to the coupling of physical and chemical effects.