The invention discloses a polymetallic ore separation method for high-slurry-content copper and lead oxide. The method comprises the steps of flotation pulp preparing, copper and lead mixing roughing, copper ore and lead ore separating flotation, lead rough concentrate sifting and the like. The method has the beneficial effects that the copper ore and lead ore mixing roughing is conducted under the low-alkalinity condition, and the problems that due to the mixing roughing operation, the alkalinity is high, consequently, the slurry floating amount is large, the rough concentrate concentration ratio is low, and the lead ore recycling rate is low are solved; the copper and lead mixing rough concentrate is directly subjected to the technology that copper ore and lead ore separation is conducted, tailings are separated and then lead flotation is conducted, the copper and lead separation efficiency is effectively improved, the problem that in the copper ore and lead ore mixing sifting process, floating is not easy is solved, and worsening of the copper and lead separation mineralization environment in the high-slurry-content copper and lead oxide ore closed-loop flotation circulating process of slurry is effectively avoided.