The present invention is to provide a notification system for timed power supply, which includes a timed power supply device and a wireless notification device. The timed power supply device is able to receive a set time inputted by a user and stores the set time into a memory module, and then starts timing, providing power supply and generating an elapsed time, respectively. When the timed power supply device determines that the difference between the elapsed time and the set time reaches a threshold value, the timed power supply device issues a notification signal through a wireless transmitter module to the wireless notification device carried by the user, so as to ensure that the user will be notified, via an alert signal generated by the wireless notification device according to the notification signal, that the set time is coming to an end.