Optical properties silica - polymeric optical fiber with a core with a diameter of 430 microns and the reflecting cover 70 microns thick from thermoplastic copolymer of a tetraftoretilen with ethylene (Tefzel brand) are experimentally investigated. The polymeric cover is applied on silica fiber with applicator from polimer melt directly on drowing tower. Optical losses of the fiber, a numerical aperture and its dependence on fiber length are measured. It is established that at propagation of light in fiber its noticeable scattering is observed. It is connected with crystallinity of polymeric cover. Distribution of intensity of scattered radiation along an axis of fiber and an indicatrix of dispersion of radiation by a coating are measured. Relative deposits of dispersion and absorption of light in a cover at the general optical losses of fiber are estimated. The possibility of use of optical fibers of this structure in laser medicine is considered.