The invention provides an ultra-thin keyboard switch. A keycap is provided with a cap top, and a surrounding wall arranged around the cap top in an extruding manner; a balance rod is provided with an intermediate part, a first bending part and a second bending part that are bent in the same direction from the two ends of the intermediate part respectively, and a first hook part and a second hook part that extend relatively from the end parts of the first bending part and the second bending part respectively; the intermediate part is clamped in a holding space among a first side edge holding wall, a second side edge holding wall and the surrounding wall; an intermediate accommodation cavity is arranged in the middle of a rubber cover for accommodating a matched handle; in addition, a side edge groove corresponding to a peripheral platform is arranged on the edge on one side; the side edge groove and the peripheral platform jointly form a clamping hole; and the first hook part and the second hook part of the balance rod are arranged in the left end and the right end of the clamping hole respectively. With the adoption of the ultra-thin keyboard switch, a clamping stagnation problem in a use process of the keyboard switch can be improved obviously, and the keyboard switch keeps smooth in a striking use process.