Abstract: A key switch assembly of the present invention comprises a housing, first and second contacts, and a metal dome. The housing forms an aperture inwardly recessed from a side surface thereof. The first and second contacts are partially received in the housing and include first and second contact portions, first and second mounting portions for being mounted on the circuit board, and first and second connecting portions respectively connected between the first and second contact portions and the first and second mounting portions. The metal dome is securely received in the aperture of the housing and includes a base and a mating portion extending from the base. The mating portion contacts the first contact portion of the first contact and the base contacts the second contact portion of the second contact when the metal dome is depressed.