A fixing member (100) of a rack server includes a chassis slide assembly (200), a main body (102), and a fixing column (110). The main body (102) is disposed on an end of the chassis slide assembly (200), one side of the main body (102) is connected to a first positioning element (104), and another side of the main body (102) is connected to a second positioning element (106). The second positioning element (106) is disposed corresponding to the first positioning element (104). The fixing column (110) is disposed on the main body (102) and one end thereof is fixed onto the chassis slide assembly (200). The main body (102) is able to rotate along the fixing column (110) as an axis. The first positioning element (104) and the second positioning element (106) have different shape. Therefore, the same chassis slide assembly (200) can match a different server rack.