In this work 28 nematode samples from amphibians, reptiles, birds and mammals captured in the State of Amazonas, Brazil, and deposited in the Helminthological Collection of the Oswaldo Cruz Institute between 1927 and 1955, were studied. Oswaldocruzia sp. and Physaloptera sp. (from amphibians), Skrjabinura spiralis Gnedina, 1933 (from birds), Mammomonogamus laryngeus (Railliet, 1899) Ryzikov, 1948 and Trichuris gracilis (Rud, 1819) Hall, 1916 (from mammals) are reported from the State of Amazonas for the first time. Oswaldocruzia mazzai Freitas & Lent, 1935, Oswaldocruzia lopesi Travassos, 1938, Aplectana membranosa (Schneider, 1866) Miranda, 1924, Physaloptera retusa Rudolphi, 1819, Capillaria sp., and Cosmocerca sp. (from amphibians), Diplotriaena bargusinica Skrjabin, 1917 and Porrocaecum sp. (from birds), Dipetalonema graciliformis Freitas, 1964 and Monodontus sp. (from mammals) represent new hosts and a new geographical distribution. Kalicephalus subulatus Molin, 1861 (from reptiles) is reported from a new host.