The Guiana dolphin (Sotalia guianensis) is a small odontocete distributed from Santa Catarina state, Brazil, to Honduras. Although it is currently considered “near threatened” by the International Union for Conservation of Nature, considerable knowledge on health and disease aspects of this species has been gained over the last decade. The main threats for the species are represented by multiple anthropic factors. Guiana dolphins feed on a variety of taxa, primarily teleosts, crustaceans, and cephalopods. Herein, we reported a case of severe laryngeal displacement and esophageal impaction with ulceration associated with a deglutted adult leatherjacket (Oligoplites sp.). This fish species is not a common prey item of Guiana dolphins’ diet. Severe upper aerodigestive compromise likely led to death by mechanical asphyxia (choke) in this dolphin. This report attested the occurrence of upper aerodigestive dysfunction due to overzealous feeding in Guiana dolphin and contributed to general knowledge on pathology of the species.