For a large-aperture radio telescope, the working frequency of the feed and receiver determines its working range and capability. Many telescopes are designed with relatively few feed sources. With the development of deep space explorations and astronomical technologies, the existing feed of the antenna cannot meet the needs of observation tasks. To further adapt to the needs of the lunar exploration project, deep space explorations, and other astronomical observations, the feed of the 40 m antenna was upgraded with multiple feeds and feed switching systems. Based on not changing the existing antenna structure, the original S/X dual band feed is removed, a new S/X dual band feed is installed, C band and Ku band feeds are added, and rapid electrical switching of three feeds was realized. This paper gives a detailed design scheme and an implementation scheme of the feed-switching system. After being upgraded, the performance indexes of the antenna meet requirements, and the 40m telescope has multi-band reception capability, which lays a foundation for making the best of the telescope and making more scientific research outputs. © Published under licence by IOP Publishing Ltd.