A switch-on/off vibrating alert device, particularly the device capable of producing a vibrating alert when a switch turns on or off a power supply, and the device comprises: a touch device installed onto a switch casing and provided for a human hand to touch in order to turn on/off the switch, and the casing includes a vibrator for generating a vibration when a control for an operation of turning on/off the switch is received from the touch device, and driving the casing and the touch device to vibrate synchronously, and users can know whether or not the switch has turned on or off the power through the vibration, and thus improving the convenience of the use.