Isospiridae is an extinct family of fossil sea snails, Paleozoic gastropod molluscs.
This family is unassigned to superfamily. This family has no subfamilies according to the taxonomy by Bouchet & Rocroi (2005). It is classified as "Basal taxa that are certainly Gastropoda" by Bouchet & Rocroi (2005).
Peter J. Wagner consider Isospiridae as synonym of Cyrtonellidae within Tergomya, The Paleobiology Database has become adatapted to this unpublished opinion by Wagner. This alternate taxonomy is as: Tergomya, Cyrtonellida, Cyrtonellidae.