A cabinet for installing first servers or second servers different than the first servers in size, and the cabinet includes a frame and four adjusting assemblies respectively installed to four corners of the frame. Each adjusting assembly includes a first mounting bracket fixed to the frame and a second mounting bracket rotatably connected to the first bracket. When the second bracket is rotated to being received in the first bracket, the first servers can be installed to the first bracket. When the second bracket is rotated away from the first bracket, the second servers can be installed to the second bracket.