A safety switch for controlling electric current between a plug and an appliance comprises generally an upper casing and a lower casing, a pair of copper conduct plates and a swivel disk member rotatably disposed into the casings. The improvement is characterized in that the pair of copper conduct plates each has a pair of staggered tip points pierced into a electrical cord having their flat portions parallel to the longitudinal axis of the cords. So that the tip points will not cut off the wires but stably engage with and grip a certain amount of the wires inside the cord in order to ensure an eligible conductivity of the electricity between the plug and the appliance.