Feeding studies of pelagic sharks in Chilean waters are rare because of the difficulty in accessing and collecting stomachs. This paper is the first contribution to the knowledge of the diet of juvenile P. glauca (Linnaeus, 1758), caught in the coastal zone of central-southern Chile. We described the diet of 13 juvenile P. glauca using frequency of occurrence, percent by number and weight quantitative indexes. The relationship between prey size and number and predator size was quantified with correlation analysis. Only 77% of stomachs had food contents. One hundred percent of stomachs contained Engraulis ringens and 60% had Dosidicus gigas. The relationship found between predator and prey size reinforces the hypothesis of positive relationships between predator and prey body size