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Instead of their forming small local groups, as occurs in other Tupi groups of the region, the Suruí have only one big village, called okara, rectangular in shape, with a central plaza on which they hold their rituals.

In the past, agriculture was their principal economic activity. They made large gardens, where they planted various kinds of manioc, bananas, sweet potatoes, corn, pepper, cotton, and tobacco. Hunting activities were quite productive in a region where tapirs, deer, peccary, wild pigs, paca, armadillo, monkeys and cotias were abundant. Among birds, they preferred the curassow and the jacu, but in time of necessity they also consumed macaw and various species of parrots. Fishing was an activity of little importance, since they lived at a distance from the large rivers. Gathering complemented the search for food. These days, their food diet has been modified by the scarcity of game and by the introduction of a poor cattle-raising, and the cultivation of rice.

Like other Tupi groups, they have a rule of partilineal descent, connected to the transmission of kinship only on the paternal side and to the idea that the man is the principal partner responsible for procreation. Due to the strong connection existing between the father and the newborn, they have the custom of the couvade which makes post-partum restriction more important for the father than for the mother.

They are divided into five patrilineal descent groups: Koaci-arúo (coati), Saopakania (hawk), Pindawa (palmtree), Ywyra (wood) and Karajá (descendants of a "Karajá" Indian, probably Xikrín, taken prisoner by the Suruí). Genealogies indicate the existence of two more groups, Sakariowara and Uirapari, today extinct. There are also indications that the Saopakania and the Ywyra have subgroups. The existence of exogamy among the groups, besides other characteristics, permits them to be classified as clans.

Chieftainship is inherited and exclusive to the men of the Koaci clan. The name for chief is morobixawa. This word could be translated as "big", and is also present in the name for full moon, sahi morobixawa. Immediately before contact, the Suruí were led by Musenai, an elderly chief who died in the epidemic of 1961. He was succeeded by his son Kuarikwara, who died a short time later. Apia, the son of Kuarikwara, was very small and could not assume the post of chief. With the lack of Koaci men, Uareni, a Saopakania, assumed the post of chief. At the beginning of the 70s, when they were involved in the guerilla wars of the Araguaia, they felt the need for a chief who knew the whites well; thus Amaxu, a Karajá, assumed the chieftainship and led the group in its most difficult moments. But, in that time, if someone asked the Suruí who was their morobixawa, they answered by pointing to Apia. When Apia reached adult age, he was recognized as chief, but he showed not even the least interest for the post, thus he was substituted by Mahyra, a Koaci, grandson of Kwarikuara's brother, Sarakoa, who also died at the beginning of the 60s.

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In the past they practiced polygyny, but the shortage of women, which actually produced polyandric unions, that is, the possibility for a married woman to have as another sexual partner a single man, made polygyny become inoperant as a practice. Preferential marriage is with mother's brother's daughter, father's sister's daughter, or sister's daughter. The residence rule was patrilocal; today the newly-weds tend to set up a new residence.

Their kinship terminology is Iroquoian. Thus, in generation 0, a man calls brother and sister, not only the children of his own parents, but also his mother's sister's children, and his father's brother's children; mother's brother's children and father's sister's children are called by another term. In the first ascending generation, father and father's brother's are called by the same term; mother and mother's sisters are called by another term, while mother's brother and father's sister are called by different terms. In the first descending generation, they use the same term for son and brother's son, and the same for daughter and brother's daughter; son and sister's daughter are called by another term which makes no differentiation by sex. In the second ascending generation, all men are called by a term equivalent to grandfather and all women by a term equivalent to grandmother. In the second descending generation, there is only one generic term applied to the individuals of both sexes.

The Suruí have an apparently limited stock of proper names, which results in many repetitions in the genealogies. A boy receives a name at the moment of birth, generally with a playful or joking meaning, and receives his permanent name in the ritual of piercing of the lower lip, when he reaches the approximate age of 13 or 14 years.