Totiviridae is a family of double-stranded RNA viruses. They are non-enveloped, icosahedral viruses. The virion is composed of a single capsid protein and is about 40 nanometers in diameter. The capsid has a T=2 symmetry.
The genome is composed of a linear double-stranded RNA molecule of 4.6–6.7 kilobases. It contains 2 overlapping open reading frames (ORF)—gag and pol—which respectively encode the capsid protein and the RNA-dependent RNA polymerase. Some totiviruses contain a third small potential ORF.