A keyboard key capable of lowering its overall height, which comprises a key cap body and a key cap base being coupled to the keyboard and disposed at the areas of four corners correspondingly having a displacing pillar and elevating groove, and an accommodating section of an electrically conductive cap body disposed at the corresponding central position of the key cap base and the key cap body, and a fixing section and a positioning section coupled to the key cap body and the key cap base respectively, and the displacing pillar and elevating groove are disposed separately at the four corners to reduce the moment of any point of the key cap body pressing the electrically conductive cap body in order to achieve the purposes of effectively lowering the overall height of the key and making the keyboard thin.