Abstract: The present invention is directed to a prosthetic cooling liner system for reducing heat and sweat for an individual's residual limb. The prosthetic cooling liner system uses fluid conduit with a prosthetic silicone liner. The fluid conduit allows for cooling fluid to flow across the residual limb, cooling the skin's surface and thereby reducing sweat produced. The cooling fluid is contained in a reservoir in a small backpack worn by the individual. A peristaltic pump is used to pump the cooling fluid from the reservoir through the embedded tubes. Such a system allows the individual to maintain a high level of activity as well as comfort, while wearing the prosthetic.