The Cong mainly cultivate burnt-over land using traditional slash and burn techniques. They make holes in the ground for seeds with sticks. Recently, they have begun using oxen or buffaloes to draw ploughs. Apart from this, agriculture, food gathering and fishing play a major role in Cong life. The Cong catch fish by hand or by using poisonous plants.

Cong women are unfamiliar with weaving. They grow cotton then use it to barter for cloth. Cong men and women are skilled at basketry, particularly making rattan mats with red dye.

The Cong live in stilt houses. Each house comprises three or four bays separated by partitions. The central bay is reserved for receiving guests. There is only one door in one end of the house and one window placed in the central bay.

Each Cong lineage has a leader and its own customs of  ancestors worship. The patriarchal nuclear family is the basis of their society. When the father dies, his eldest son will take his position in the family.

In the past, the Cong could only marry within their ethnic group. More recently, they have accepted marriage with members of other groups such as the Thai and Ha Nhi. The man's family proposes marriage. After the betrothal, the man lives with his future wife's family for several years and the woman wears her hair knotted in a chignon on the top of her head, which shows that she is married. The wedding is often celebrated when the couple has children. Then the man must offer silver and a certain amount of other cash to the parents of his wife. Several days after the wedding, the couple comes to visit the family of the wife.

The Cong have their own calendar. A year has 12 months (each corresponding to an animal) and a month has 30 days.

The Cong's ancestors belonging to the second or third generation are worshipped. A ritual sacrifice to the souls of the ancestors is performed several times a year at weddings, after harvest, at the birth of the child or upon the death of a relative. Like the Ha Nhi and La Hu, every year each Cong village holds a communal ceremony for the start of a rice crop. Several other rites are also held to pray for bumper crops and prosperity.

The Cong folk arts are diverse with beautiful melodies and alternating songs that they like to sing at the communal ceremonies.