Utilization of optical fiber involves two problems: the use of a protective shell (mainly various types of plastics) and the actual optical fibersquartz filaments with an admixture of germanium dioxide coated with a protective layer of polyethylene. The aim of the work was to study the physical and chemical properties of samples of optical fiber wastes. The behavior of the components of this material has been studied by thermography: a quartz germanium-containing glass and a polyethylene sheath during heat treatment. It has been established that in the temperature range from 20 to 700 °С in the atmosphere of the air quartz fiber does not undergo changes, and the polyethylene shell of the optical fiber passes through the stages of sorption of water vapor and air oxygen at 125 and 200 °С during melting, and above 300 °С – destruction with a mass loss of up to 55 % and the release into the gas of products of oxidative degradation.