At　present,　there　is　still　a　lack　of　monitoring　of　the　gases　produced　in　the　flotation　process　in　mines.　As　these　gases　with　low　concentration　are　mainly　produced　by　flotation　reagents,　and　the　single　metal　oxide　semiconductor　based　gas　sensors　are　difficult　to　meet　the　requirements　of　use.　Activated　carbon　is　a　porous　material　that　is　cheap　and　widely　available,　which　can　make　enough　flotation　gases　adsorb　on　the　surface　of　gas　sensing　materials　and　change　the　sensor＇s　conductivity　obviously.　In　this　work,　ZnO/activated　carbon　composites　were　synthesized　by　a　facile　one-pot　hydrothermal　method.　The　crystal　structure,　morphology,　nanosize　and　chemical　composition　of　the　samples　were　investigated　by　XRD,　FESEM,　TEM,　Raman　spectroscopy,　XPS　and　BET,　respectively.　The　results　showed　that　the　gas　sensing　materials　based　on　ZnO/activated　carbon　composites　were　able　to　detect　the　flotation　gases　such　as　butyl　xanthate　and　terpineol.　The　gas　sensor　based　on　ZnO/activated　carbon　(10/1.5)　composite　reached　the　best　response　value　of　28.90　at　75　degrees　C　for　1　ppm　butyl　xanthate　gas,　8.67　at　100　degrees　C　for　0.5　ppm　terpineol　gas,　as　well　as　good　reproducibility,　which　is　potential　for　practical　detection　of　flotation　gases.