Phosphate glass samples doped with Gd2O3 and Tb2O3 oxides were synthesized and studied towards potential application in high dose radiation measurements. Glass/polytetrafluoroethylene composite detectors were prepared and used to study dosimetric signal dependencies, and thermoluminescence dosimetry (TLD) technique was used as a main investigation tool to study detectors response. Influence of dopants and polymer on TL signal were investigated. The dosimetric properties, like dose response, linearity and signal stability of the composite dosimeters were investigated. Incorporation of lanthanide oxides into glass matrix changes substantially the thermoluminescent behavior of phosphate glass. The highest luminescence yield exhibits glass doped with terbium oxide. Negligible influence of polytetrafluoroethylene agglutinator on dosimetric signal was observed. Dependence of the integrated thermoluminescent signals for all samples vs. absorbed dose can be considered as linear. The new phosphate glass-polytetrafluoroethylene composites show good material and thermoluminescent properties for the high gamma and electron beam dose measurement applications.