A cable management assembly, comprising: a first arm including a first connecting structure; and a cable management device configured to be mounted on the first arm; wherein the first connecting structure of the first arm includes a first mounting hole and a first positioning hole, and the first mounting hole includes a first hole portion and a second hole portion, and that the cable management device includes a wall, a first mounting portion, and an elastic portion, and wherein the first mounting portion is connected to the wall and includes a first extension section and a second extension section bent with respect to the first extension section, and wherein the elastic portion is disposed on the wall, wherein the elastic portion of the cable management device includes a connecting section and an elastic section, the connecting section is disposed on the wall, and the elastic section is connected to the connecting section and is provided with an engaging feature; wherein the first extension section of the first mounting portion of the cable management device is able to enter the second hole portion of the first mounting hole of the first arm from the first hole portion, in order for the second extension section of the first mounting portion to be blocked by a first blocking section adjacent to the second hole portion of the first mounting hole, and for the cable management device to be mounted to the first positioning hole through the engaging feature of the elastic section; wherein the first arm has an upper wall, a lower wall, and an extension wall connected between the upper wall and the lower wall, the cable management device includes a releasing portion connected to the elastic section of the elastic portion such that the engaging feature is disposed between the connecting section and the releasing portion, characterized in that the releasing portion extends when mounted beyond one of the upper wall and the lower wall, and the releasing portion is configured to operate the engaging feature of the elastic section of the elastic portion in order to disengage the engaging feature from the first positioning hole; wherein the elastic section is tilted outward at an angle with respect to a wall surface of the wall, and the one of the upper wall and the lower wall has a notch for receiving the releasing portion. a first arm including a first connecting structure; and a cable management device configured to be mounted on the first arm; wherein the first connecting structure of the first arm includes a first mounting hole and a first positioning hole, and the first mounting hole includes a first hole portion and a second hole portion, and that the cable management device includes a wall, a first mounting portion, and an elastic portion, and wherein the first mounting portion is connected to the wall and includes a first extension section and a second extension section bent with respect to the first extension section, and wherein the elastic portion is disposed on the wall, wherein the elastic portion of the cable management device includes a connecting section and an elastic section, the connecting section is disposed on the wall, and the elastic section is connected to the connecting section and is provided with an engaging feature; wherein the first extension section of the first mounting portion of the cable management device is able to enter the second hole portion of the first mounting hole of the first arm from the first hole portion, in order for the second extension section of the first mounting portion to be blocked by a first blocking section adjacent to the second hole portion of the first mounting hole, and for the cable management device to be mounted to the first positioning hole through the engaging feature of the elastic section; wherein the first arm has an upper wall, a lower wall, and an extension wall connected between the upper wall and the lower wall, the cable management device includes a releasing portion connected to the elastic section of the elastic portion such that the engaging feature is disposed between the connecting section and the releasing portion, characterized in that the releasing portion extends when mounted beyond one of the upper wall and the lower wall, and the releasing portion is configured to operate the engaging feature of the elastic section of the elastic portion in order to disengage the engaging feature from the first positioning hole; wherein the elastic section is tilted outward at an angle with respect to a wall surface of the wall, and the one of the upper wall and the lower wall has a notch for receiving the releasing portion.