Abstract: In view of the nuclear radiation payload on the Chang'e-3 probe, the targeted protection should be taken during the assembly process to reduce the radiation hazard on personnel. In this paper, by analyzing the effects of the radiation dose rate on different working platforms, combined with the general protection method, a radiation protection design scheme is proposed, based on the time control, the operating distance limit and the shielding choice involved in the nuclear assembly. Through the simulation-based verification and the final implementation results, it can be confirmed that the protection design scheme is reasonable and feasible, the cumulative radiation dose on personnel falls within the expected value and in the range of a low level.