Twenty-seven communities of indigenous groups in the Amazon region northeastern Ecuador participated in an ethnobotanical study in the area of influence of PetroEcuador, the state petroleum company, including the ethnic groups Kichwa (8 communities), Secoya (3), Shuar (5), Siona (4) and Waorani (7). The present contribution reports on the uses of 42 species of ferns and 7 species of fern-allies by these ethnic communities. A total of 40 species were identified to the species level, and seven taxa were identified to genus (Asplenium, Campyloneurum, Elaphoglossum, Polypodium, Selaginella, Tectaria, Terpsichore). Medicinal uses were recorded for 29 species, two for food, and one each for handcrafts and ritual uses; the majority of species are also used as ornamentals. The majority of medicinal uses of ferns and fern-allies were  reported for Kichwa communities (18 species), followed by Waorani communities (7 species), and Shuar communities (4 species).En las 27 comunidades étnicas Kichwa (8), Secoya (3), Shuar (5), Siona (4) y Waorani (7) que participaron en el estudio de Etnobotánica de las Comunidades Indígenas del Nororiente Ecuatoriano en el Área de Influencia de Petroecuador en la  Amazonía Ecuatoriana se registró para el uso etnobotánico 42 especies de helechos y 7 afines, de las cuales 40 fueron identificadas hasta especies y los demás hasta género (Asplenium, Campyloneurum, Elaphoglossum, Polypodium, Selaginella, Tectaria, Terpsichore); por otro lado 29 especies son de uso medicinal, dos alimenticio, uno artesanal, uno mítico; y la mayoría son utilizados como ornamentales. La comunidad Kichwa es la que presenta más registros botánicos de helechos usados medicinalmente (18 especies), seguida por las etnias Waorani (7) y Shuar (4).