Organic-inorganic perovskites have shown to be promising materials with great potential for use in radiation detection, in which higher energy photons or heavy charged alpha particles need to be detected. Halide-based rudorffites and double perovskites are suitable candidates for X- and γ-radiation detectors due to their relatively high atomic number and thus high stopping power, superior carrier life-time product, tunable band gap, and low temperature fabrication process. In this study, high-resistivity MAPbBr3 single crystals are investigated. Current– voltage characteristics of the ITO/PTAA/MAPbBr3/C60/BCP/Cu detectors were analyzed. The main parameters of the crystals and barrier structures were determined. The charge transport mechanisms in the investigated structures within the entire voltage are well described in terms of the well-known theoretical models. The obtained electrical performance parameters indicate that the MAPbBr3 single crystals satisfy requirements for radiation detection application. The contacts to the MAPbBr3 crystals need optimization in order to decrease the leakage current through the barrier structures, and thus to improve the energy resolution of the detectors