This study constitutes a new biostratigraphic approach from an outcrop of the Itaituba Formation, in the Itaituba City, southern Amazonas Basin, Pará State, Brazil, integrating conodont and palynological data. Conodont associations includes Idiognathodus incurvus, Idiognathoides sinuatus, Adetognathus lautus, Hindeodus minutus, Diplognathodus coloradoensis, D. orphanus and D. ellesmeremsis. Among the palynomorphs, Costatascyclus  crenatus, Protohaploxypinus amplus, Spelaeotriletes arenaceus, S. triangulus, Meristocorpus explicatus, Striomonosaccites incrassatus and Meristocorpus sp. B constitute important biostratigraphic species, suggesting a middle Atokan age for the study section, in agreement with conodont biostratigraphy.This study constitutes a new biostratigraphic approach from an outcrop of the Itaituba Formation, in the Itaituba City, southern Amazonas Basin, Pará State, Brazil, integrating conodont and palynological data. Conodont associations includes Idiognathodus incurvus, Idiognathoides sinuatus, Adetognathus lautus, Hindeodus minutus, Diplognathodus coloradoensis, D. orphanus and D. ellesmeremsis. Among the palynomorphs, Costatascyclus crenatus, Protohaploxypinus amplus, Spelaeotriletes arenaceus, S. triangulus, Meristocorpus explicatus, Striomonosaccites incrassatus and Meristocorpus sp. B constitute important biostratigraphic species, suggesting a middle Atokan age for the study section, in agreement with conodont biostratigraphy.