A small Masked Booby (Sula dactylatra) colony was found on the southeast portion of Isla Lobos de Tierra, Peru. It consisted of 10 pairs of birds distributed in 4 areas. Five pairs were in a single nesting area in a ravine, 2 of the pairs were protecting single chicks. The other 5 pairs were found in 3 areas nearby. Sites faced southeast, exposed to the dominant winds. The breeding location is on the coastal zone of cold waters; highly productive waters of the Peruvian Upwelling System. Even though flying fishes and sardines are the most common prey items of Masked Boobies on their main breeding areas, on Lobos de Tierra they feed mainly on Peruvian anchovies. Possible causes of this colonization are discussed.