The Matsés practice slash-and-burn agriculture, normally in an area located outside of the village. Their diet consists of plantain, corn, and manioc supplemented with forest fruits, fishing, and hunting. The principal drinks of the Matsés are chapo, prepared from boiled plantain, and chicha, which is made from dried corn and plantain.

In Amazonian communities, small-scale farming—or chacra—is a way of life. The Matsés people use slash-and-burn techniques to establish these gardens, typically placing them a short walk or canoe ride from home. In these chacras, they grow a wide variety of food crops, including staples such as plantain and cassava. Most days, women and children head to the chacras to harvest food for the family. Beyond providing sustenance, these gardens serve as outdoor classrooms where mothers pass down vital agricultural knowledge and traditions to their daughters and future generations.

Chapo is drunk on a daily basis in the villages. As relatives and friends visit one another's houses, chapo will often be offered; be it morning or night, the drink plays a central role in Matsés culture. Made by boiling plantains, the watery mixture is strained through a naturally woven sieve or secte, to produce a deliciously sweet drink that can be consumed both hot and cold.

Well known throughout South America, chicha is a fermented or non-fermented drink made from different grains, maize and fruits. Different cultures have their own way and style of making chicha, the Matsés for example use a combination of dried corn and plantain in their recipe.

Corn which has been dried above the fire is separated into a wooden trough where it is crushed using a large, heavy wooden paddle in a laborious rocking motion. After working the corn, the plantain is added to the mix and together all the ingredients get pulverised. Water then gets added into the mixture before it is squeezed onto and strained through a naturally woven sieve called secte, made from the leaves of a long bamboo-like plant called mando-dannësh or huarumá in spanish (sp. Ischnosiphon puberulus) commonly used for basketry. The filtered liquid is the base of the chicha, and this process is repeated numerous times whereby the corn mixture is crushed again then put into the chicha water and strained again. Finally the creamy liquid is boiled over the fire before it is ready to be served.

To supplement their staple diet of plantain, corn and manioc, the Matsés will actively fish and hunt, relying on their encyclopaedic knowledge of rainforest ecology and honed hunting and fishing techniques. They hunt a wide variety of rainforest animals; primarily tapirs (donkey-sized mammals related to the rhinoceros), peccaries (reminiscent of wild boars), deer, two-toed sloths, armadillos, woolly monkeys, spider monkeys, howler monkeys, saki monkeys, uacari monkeys, capuchin monkeys, pacas (beagle-sized rodents), agoutis (smaller dog-sized rodents), curassows (similar to wild turkeys), guans (chicken-sized birds), trumpeters (terrestrial birds that travel in flocks), tinamous (partridge-like birds), wood-quails, and caimans. Being an egalitarian people, the Matsés will traditionally share the meat after a successful hunt with their next of kin.

Fish is a normal supplement to a diet of jungle meat for the Matsés. They recognise over 100 species of fish, which include wolf-fish, hatchet fish, dog-toothed fish, knifefish, armored catfish, peacock bass, piranhas, freshwater stingrays, and electric eels. Fishing today is more commonly practiced with a hook and line, but they also possess an ingenious method that involves the use of a toxic plant.

This toxic plant is known as chiun in Matsés (huaca in local Spanish; Latin: Cliabadium remotiflorum), whose intoxicating effect on the fish cause them to jump in and out of the water, allowing for easier net-catching.

This toxin eventually seeps out of the fish, returning them to their normal state and also spares the lives of the fish that are too small to eat, unlike the more toxic barbasco vine commonly utilized to poison streams in the Amazon.