Abstract: A mail delivery alert system includes a mailbox that may receive mail and the mailbox has a door. A sensing unit is positioned within the mailbox and the sensing unit senses light and motion. Thus, the sensing unit detects when the door is opened. The sensing unit generates an alarm sequence when the door is opened. An electronic device is provided. The electronic device is in electrical communication with the sensing unit. Thus, the electronic device receives the alarm sequence from the sensing unit. The electronic device issues an alert when the electronic device receives the alarm sequence. Thus, the electronic device alerts that mail has been delivered to the mail box.