The present work aims to offer a list of Arsenurinae and Ceratocampinae species known to occur in Rio Grande do Sul, Brazil. The list is based on bibliographical data, newly collected specimens, and previously existing museum collections. The Arsenurinae are listed in the following genera (followed by number of species): Arsenura Duncan, 1841. (4), Caio Travassos & Noronha, 1968 (1), Dysdaemonia Hubner, [1819] (1), Titaea Hubner, [1823] (1), Paradaemonia Bouvier, 1925 (2), Rhescyntis Hubner, [1819] (1), Copiopteryx Duncan, 1841. (2). Ceratocampinae are listed in Adeloneivaia Travassos, 1940 (3), Adelowalkeria Travassos, 1941. (2), Almeidella Oiticica, 1946 (2), Cicia Oiticica, 1964 (2), Citheronia Hubner, [1819] (4), Citioica Travassos & Noronha, 1965 (1), Eacles Hubner, [1819] (4), Mielkesia Lemaire, 1988 (1), Neocarnegia Draudt, 1930 (1), Oiticella Travassos & Noronha, 1965 (1), Othorene Boisduval, 1872 (2), Procitheronia Michener, 1949 (1), Psilopygida Michener, 1949 (2), Scolesa Michener, 1949 (3) and Syssphinx Hubner, [1819] (1). Rhescyntis pseudomartii Lemaire, Titaea tamerlan tamerlan (Maassen), Eacles bertrandi Lemaire, Eacles magi Schaus and Mielkesia paranaensis (Rego-Barros & Mielke) are new records for Rio Grande do Sul. To facilitate identification we provide photographs, morphological characteristics of each species, and dichotomous keys. Also, we discuss briefly their distribution and the inventorying status of Lepidoptera in Rio Grande do Sul.