A very popular belief among Vietnamese is the custom of the ancestor cult. In every household, an ancestor altar is installed in the most solemn location.

Vietnamese believe that the soul of a dead person, even if dead for many generations, still rests along with their descendants on earth. The dead and living persons still have spiritual communion; in everyday life, people must not forget that what they enjoy and how they feel is the same for their dead relatives.
On the last day of every lunar year, an announcing cult, cung tien thuong, is performed to invite the dead forefathers to return home to celebrate Tet holidays with their families. During the last days before Tet, all family members visit their ancestors� graves; they clean and decorate the graves, in the same manner that the livings clean and decorate their houses to welcome the New Year.

On the anniversary of an ancestor�s death, descendants and relatives unite and prepare a feast to worship the dead people and to ask for health and happiness for themselves. From generation to generation, ancestor worshipping customs have been religiously preserved. There are some small variations between those customs among the many Vietnamese ethnic groups, but the common theme of fidelity and gratitude towards the ancestors remains.