The Instituto Butantan (pronounced [ĩʃtʃiˈtutu butɐ̃ˈtɐ̃]) is a Brazilian biologic research center located in Butantã, in the western part of the city of São Paulo, Brazil.

Instituto Butantan is a public institution affiliated with the São Paulo State Secretariat of Health and considered one of the major scientific centers in the world.

By extracting the reptiles' and insects' venoms, the Institute develops antivenoms and medicines against many diseases, which include tuberculosis, rabies, tetanus and diphtheria.

It is also a state-supported producer of vaccines against many infectious diseases, such as rabies, hepatitis, botulism, tetanus, diphtheria, pertussis and tuberculosis, as well as polyvalent and monovalent antivenoms against the bites of snakes, lizards, bees, scorpions and spiders (which, historically were first developed in the beginning of the 20th century by Dr. Vital Brazil and his coworkers).

Among the distinguished scientists at the institute were biochemists Karl Slotta and Heinz Fraenkel-Conrat, pioneers in the study of progesterone, estriol, and medical use of venom, from 1935 to 1948.

[4] The production units manufacture the following bioproducts: The Butantan is one of the major touristic and educational attractions in a vast park area in the city section of Butantã in São Paulo.

The Fundação Butantan is a non-profit corporation established in 1984 by Prof. Willy Beçak to use more efficiently public funds and capital investments made by the Ministry of Health for the production of immunobiologicals.

Part of the funds are used in the Institute for research and cultural activities, as well as to provide its workers with meals and basic food supplies.