Bornellidae is a family of nudibranch sea slug - marine gastropod molluscs in the superfamily Dendronotoidea.

This family is within the clade Cladobranchia (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005).

Nudibranch species within the Bornellidae family have elongated bodies, with pairs of cerata-like dorsal and lateral appendages, with finger-like branches, running along the length of the body.

Their rounded head has a tentacle on either side of the mouth, with tiny finger-like papillae.

Nudibranchs within this family are believed to feed exclusively on hydroids.