A general description of gillnet fisheries in the Southeast Pacific area (comprising the waters of Ecuador, Peru and Chile) is presented and their potential threat to cetaceans is discussed. Information was gathered mainly through a literature review and interviews with fishermen and fishery experts but direct observations are included where possible. Gillnets are the main fishing gear used in waters of the region. In Peru they represent around 60% of the fishing gear used. Mortality of small cetaceans in fishing nets is known to be high in Peruvian waters where a market for their meat exists. An unknown number of large and small cetaceans are taken incidentally in the gillnet swordfish fishery in Chilean waters. Some tens to a few hundred dolphins and porpoises die every year in southern Chile in an expanding coastal gillnet fishery for ratfish and sciaenids. The scanty information from Ecuador suggests that a few hundred animals may get entangled in fishing nets every year. No foreign driftnet fisheries operate in or off the waters of the region. Little specific information on gillnet fisheries is available as they are pooled with other fisheries as ‘artisanal’ by national agencies. It is recommended that national agencies institute studies to evaluate the impact of gillnet fisheries on small cetaceans and other marine organisms, including commercially exploited species. Research on alternative fishing methods should be considered in order to reduce cetacean mortality without damaging the fisheries.