In December 2001, an outbreak of foodborne gastroenteritis infected 114 of 161 people who ate at a restaurant in Aracaju, State of Sergipe, Brazil. Methods: The epidemiological and microbiological aspects of the outbreak were characterized. Results: Potato salad made with homemade mayonnaise and stored at unsuitable temperatures was associated with increased risk of foodborne infection. Salmonella Enteritidis was isolated from the diarrheal stools of the hospitalized patients, and genotyping of the fecal samples generated identical randomly amplifi ed polymorphic deoxyribonucleic acid (DNA) profi les. Conclusions: To the best of our knowledge, this is the fi rst and the only record of a gastrointestinal outbreak in Sergipe.