Xeneichthys is an extinct genus of teleost fish from the Albian El Doctor Formation in Hidalgo, Mexico. The type and only species, X. yanesi, is known from multiple specimens, representing the entire body.
Xeneichthys is known from several specimens from a locality called the Muhi Quarry. The holotype, UAHMP 1063, represents a complete specimen. The average length of the species is , however some sampled individuals reached up to .
The generic name, Xeneichthys. 'Xene' comes from the Otomàword meaning 'big mouth', while 'ichthys', originates from the Ancient Greek word meaning 'fish'. The specific epithet, yanesi, honors the Yáñez family, who worked at the quarry the specimens were found in.