Abstract: A perpetual calendar, particularly a perpetual calendar that can be electrically operated to show the date, the week-day, and the month. The calendar comprises a round wheel or case driven by a gear to rotate one cycle per 24 hours, and the peripheral edge of the round case has a cam for contacting a micro-switch which can trigger a circuit to drive a motor for rotating an eccentric wheel. A retractable rod can be driven by a pin on the eccentric wheel and move downwards to pull the date pulling rod and the week-day pulling rod downwards, and then a ratchet wheel will be driven to rotate, and a positioning piece in the notch of the ratchet wheel will cause the loose-leaves showing date and week-day to advance.