Eurata patagiata Burmeister is a diurnal moth of the Arctiinae subfamily of Eribidae. The chemical nature of pheromones of the family has not been well studied. Calling behavior was observed. Using several chemical techniques (gas chromatography-EI-mass-spectrometry, retention indices, micro-reactions, and synthesis) and bioassays with an olfactometer and in the field, (Z, Z, Z)-9,12,15-octadecatrienal (linolenal) and (Z, Z, Z)-9,12,15-octadecatrienol (linolenol) were identified as the main sex pheromone compounds in extracts from the female glands. Behavioral assays showed that more than 90% of male moths were attracted to a mixture of the pheromones rather than to hexane (check). However, the percentage decreased when only one compound was assayed. Preliminary field experiments demonstrated that males were captured in pitfall traps with a mixture of the pheromone compounds.