Ancestor worship of Miao Ethnicity, also called "Drum Commune Festival", "Drum Commune Memorial Ceremony" "Drum-worshipping Festival" or "Bull-sacrificing Festival", is a religious activity passed down from the clan society. Among varied ancestor worship ceremonies, that of killing bulls by Miao people boasted the longest history, a grand scale and a solemn ceremony.

As legend has it, in ancient times, the ancestors of Miao Ethnic Minority migrated to Guizhou from afar. During the long migration, spirits of the deceased stayed with the group in the form of ashes preserved in the drum. Bull sacrificing means to worship the ancestors by killing bulls. Usually there is a small-scale ceremony every thirteen years and one large scale every fifty years. According to conventions, it is through divining that the powwow decides beforehand in which year and at what time the ceremony will be held, be it regular or irregular. On the eve of Bull-sacrificing Festival, every family has to worship their ancestors by killing bulls, thus costing a lot. Usually the ceremony is held at the time of a good harvest. Otherwise, it will be postponed.

There are a great many complicated procedures during the ceremony. Miao people who participate in it are expected to fulfill their own roles while following the procedures. The major procedures include electing the leader, transferring a pair of drums from the previous leader to the newly-elected one, turning over the drum preserved in a grotto, cutting down a tree for making a new drum, killing bulls and offering sacrifices to the ancestors, and finally sending the new drum to the grotto. Every procedure is further divided into several minor activities. Altogether a ceremony will take four years, with two activities-killing bulls and offering sacrifices-as the highlights.