The recently developed ‘n’ on ‘p’ type silicon solar cell has been evaluated for application as a high-level gamma-radiation dose-rate meter. The solar-cell ionization current was found to be a linear function of dose rate in a range from 102 to 107 rads per hour. A degradation rate of approximately one per cent per megarad was measured after stabilization with twenty megards of cobalt-60 gamma radiation. The system has proven to be stable over long periods of time. Temperature dependence corrections have been found to be 0.2 per cent per degree centigrade between 0 and 60 degrees centigrade.