This work documents zootherapeutic practices in Northeast Brazil. It is primarily based on field surveys carried out in fishing villages located in the states of Maranhão and Paraíba, where 60 respondents (38 men and 22 women) provided information on animal species used as medicine, body parts used to prepare the remedies and illnesses to which the remedies were prescribed. A total of 100 animal species (72 families), distributed in 12 taxonomic categories, was used as medicine. Zootherapeutic resources were used to treat 62 different diseases. The local medicinal fauna is largely based on wild animals, including some endangered species. Threatened species, such as the seahorse (Hippocampus reidi, Ginsburg, 1933) (Syngnathidae) and the green turtle (Chelonia mydas, Linnaeus, 1758) (Cheloniidae) represented important medicinal resources for the studied communities. This shows the need to integrate traditional knowledge into strategies to conserve and manage faunistic resources in Brazil.