The Hall for Ancestral Worship (Fengxian Dian) stands to the southeast of the Hall of Heavenly Purity, with the Six Eastern Palaces to its north. Built in 1656 during the Qing Dynasty (1644-1911), the hall was where emperors enshrined memorial tablets for their ancestors. The front hall and the rear hall are connected together by a hallway, thus making a whole structure. Large-scale sacrifices were held at the front hall on the Spring Festival, the Winter Solstice and on the reigning emperor's birthday. The emperors made their profound courtesies to departed ancestors at the rear hall on the ancestors' birthdays and death-days, the Lantern Festival (lunar January 15th), the Tomb-sweeping Day (solar April 4 or 5) and on Mid-Autumn Day.

Now the hall has been converted into an exhibition hall dedicated to clocks and watches. Some were manufactured by the imperial workshop or made in Guangzhou (in Guangdong Province) and Suzhou (in Jiangsu Province); others were imported from England, France, German, Swiss, America and Japan, or were sent as gifts to the emperors. They are of different shapes and styles and amaze visitors with their consummate performance. Though they were made over two thousands years ago they still work well to this day. In addition, a video system in the hall shows how these exquisite clocks operate.