Wall clock with a perpetual calendar mechanism comprising an outer case, a quartz movement, a day of the week disc, a tens disc and a units disc, a gear train for driving the discs, another gear train for driving a month indicator hand, a battery set for a clock movement, another battery set for a drive motor, a calendar cam with forty-eight interstices, the depths of the interstices are various, depending on the lengths of months spanning four years, including a leap year, and a three step cam formed on the rear surface of the units disc and a switch control assembly having a control arm which has one end thereof contacts a bottom of the interstice of the calendar cam, where the three step cam initiates an end-of-the-month day-correction mechanism.