This is a taxonomy of the insect order Lepidoptera down to family level.
Lepidoptera consists of moths (42 superfamilies), most of which are night-flying, and a derived group, mainly day-flying, called butterflies (superfamily Papilionoidea). Within Lepidoptera as a whole, the groups listed below before Glossata contain a few basal families accounting for less than 200 species; the bulk of Lepidoptera are in the Glossata. Similarly, within the Glossata, there are a few basal groups listed first, with the bulk of species in the Heteroneura. Basal groups within Heteroneura cannot be defined with as much confidence, as there are still some disputes concerning the proper relations among these groups. At the family level, however, most groups are well defined, and the families are commonly used by hobbyists and scientists alike.