The first part of the revision of genus Dellia Stål, 1878, comprising Cuba in the Greater Antilles, is presented here. Dellia insulana Stål, 1878, the type-species, is redescribed and illustrated for the first time. Dellia multicolor Carl, 1916 stat. resurr. is restored as valid species, redescribed from both sexes, illustrated for the first time, its type locality is defined and its geographical distribution is clarified. Seven new species are also described: Dellia albida n. sp., Dellia atrostriata n. sp., Dellia brauni n. sp., Dellia megalapida n. sp., Dellia melici n. sp., Dellia siboney n. sp., and Dellia zephyra n. sp. All nine species are described and compared in detail, supported by a thorough photographic complement.