A system is described for forming a debris barrier downhole in a wellbore. The system may include a mandrel, a retrievable downhole tool, and a debris ring. The mandrel may be positionable within a wellbore. The retrievable downhole tool may be positionable around the mandrel to perform tasks downhole in the wellbore. The debris ring may include an expandable material positionable around the mandrel to form a debris barrier. The debris barrier may be formed in response to exposing the expandable material to wellbore fluid.