A safety switch has a casing, a first prong, a second prong, the rocker and a pivot switch contact unit. The rocker is mounted pivotally on the top of the casing and has an arm and an end opposite to the arm. The pivot switch contact unit has a switch contact and a pull rod. The switch contact bends upward as temperature of the switch contact increases, is pivoted to the top end of the first prong and has a proximal and distal ends. The distal end of the switch contact is connected to the arm and selectively abuts the second prong. The pull rod is connected between the end of the rocker and the proximal end of the switch contact to provides the second end of the rocker a down pulling force when the distal end of the switch contact is slightly bent and not abut the second prong.