Extension module tray and extension module assembly of server, and server

The utility model discloses an expansion module tray of a server, an expansion module assembly and the server. The expansion module tray comprises a tray body, a plurality of expansion modules and a plurality of expansion modules, the tray is used for being assembled in an expansion slot of the server; wherein the tray is provided with at least one containing groove, and each containing groove is used for containing a first type of expansion modules or a second type of expansion modules. And different types of expansion modules are convenient to replace.