An improved two – phase contact oxidation adsorption integrated bioreactor (CABR) was used to treat mixed wastewater from copper mine. The CABR was made up of a biofilm reactor and an activated carbon reactor. Polyacrylonitrile balls (20 mm diameter, 260 m2/m3 specific surface, 90% porosity) were filled into the contact oxidation reactor as biofilm attaching materials. Hydraulic residence times (HRT) of the two contact oxidation reactor were 1.5 hr and 1.2 hr, separately. Relevant ratio of aeration and water of the two contact oxidation were 5:1 and 3:1. From the long-term operation, the average removal efficiencies of chemical oxygen demand (COD) and ammonia nitrogen (NH4+-N) were 84.1% and 71.3% respectively. Two – phase contact oxidation can achieve the higher removal efficiency and the lower power consumption. Additionally, the activated carbon reactor can significantly remove heavy metal.