Abstract: The feed cabin, which is placed on the Five-hundred-meter Aperture Spherical radio Telescope and located at an altitude of 140 meters, is susceptible to wind and rain loads. Excessive wind and rain vibration response will affect its normal operation. This paper established a refined finite element model of the feed cabin-cable-tower coupled system and carried out modal analysis. The results show that its fundamental frequency is very small and the modes are dense. The refinement of the feed cabin model has a great influence on the natural frequency of the structure. The wind and rain load time history was simulated to study the proportion of rain load in the wind and rain load of each component of the system. It is found that after considering rainfall, the overall load increases significantly, among which the load on the feed cabin has the largest increase.The dynamic response of the feed cabin-cable-tower coupled system under wind and rain loads was calculated. The results show that the rain load has a great impact on the displacement response of the feed cabin. The rain load has little effect on the total stress of the structure. The maximum working wind speed decreases significantly when considering the rainfall. The maximum working wind speed that meets the accuracy of the secondary fine-tuning platform is less than the working wind speed (4 m/s) for the FAST design, which greatly affects the normal operation of the feed cabin.