The invention discloses an advanced bio-treatment technology for wastewater, which can improve the biodegradability of the wastewater. According to the technology, through fixing reductive metal strips around the stirring paddle of an anoxic bioreactor and using mechanical stirring in combination, the reductive metal are reacted with oxidative matters such as dissolved oxygen in the wastewater to release metal ions slowly, thereby reducing the oxidoreduction potential of anoxic biological sludge in the reactor, and effectively improving the biodegradability to benefit the further biochemical treatment. The technology can be used for advanced treatment of wastewater discharged after routine biological treatment, and is an advanced wastewater bio-treatment technology of high efficiency, low cost, and convenient operation.