An assembling structure of a quick installation/uninstallation switch, including a layout fixing seat formed with a central opening and a transverse insertion slot intersecting the central opening. A locating member is inserted through the transverse insertion slot. The locating member is formed with a central hole corresponding to the central opening. A resilient locating member and at least one lateral projecting section with a guide slope are disposed on the circumference of the central hole. At least one resilient restoring member is disposed between the locating member and the layout fixing seat for restoring the locating member to its home position. A connecting end of a switch main body is fitted in the central opening. A lateral locating section with a guide slope is formed on a circumference of the connecting end corresponding to the lateral projecting section. A locating transverse slot is formed on the circumference of the connecting end. The resilient locating member is inlaid in the locating transverse slot.