A key assembly comprises a base plate, two elastic elements and a key body. Each elastic element has a securing portion and two compressing portions protruding from two ends of the securing portion. The securing portions are latched to the base plate. The key body is slidably mounted to the base plate between the two elastic elements. The key body includes a first key section resisting one of the two elastic elements and a second key section resisting another elastic element. When the first key section slides toward and compresses the corresponding elastic element, the second key section slide away from the corresponding elastic element.