Trogiomorpha is one of the three major suborders of barklice, booklice, and parasitic lice in the order Psocodea (formerly Psocoptera), alongside Troctomorpha and Psocomorpha. There are about eight families and more than 430 described species in Trogiomorpha. Trogiomorpha is widely agreed to be the earliest diverging of the three suborders, and retains the most primitive characteristics.

The cladogram below shows the position of Trogiomorpha within Psocodea:

Species of Trogiomorpha possess antennae that are split into 20 or more separate pieces. The tarsi are segmented into three separate equal pieces, and they have a strong posterior spine. They have been described as having a "mothlike" (brown) appearance in color.

Trogiomorpha contains three infraorders and five extant (living) families, as well as three identified extinct families: