Integrated circuits for communications play an enabling role when it comes to outer-space exploration thanks to their small footprint and low weight1–3. However, owing to the severe irradiation effects of space energetic particles, the implementation of radiation-tolerant electronic circuits remains a challenge4–6. Here we report the observation of the space radiation effect on a satellite-based device and find that atomically thin materials are expected to accumulate minimal radiation-induced damage in principle. Accordingly, on the basis of a 4-inch wafer-scale monolayer 2D MoS2 process, we implement an atomic-layer transistor-based radiation-tolerant radio frequency (RF, 12–18 GHz) system with both transmitters and receivers for spaceborne communication. For on-orbit experiments, the 2D communication system was successfully launched to the approximately 517 km low Earth orbit. Notably, the system maintains a bit error rate (BER) of less than 10−8 in the transmitted data after 9 months of on-orbit operation, indicating substantial radiation tolerance and long stability. The lifespan of the 2D communication system is predicted to be about 271 years even on the geosynchronous orbit with a much harsher radiation environment. This work showcases the unique prospects of 2D electronics for spaceborne applications.