Eosinophilic cholecystitis (EC) is a rare disease that is characterised by eosinophilic infiltration of the gallbladder. Its pathogenesis is unknown, although many hypotheses have been made. Clinical and laboratory manifestations do not differ from those of other causes of cholecystitis. Diagnosis is histological and usually performed after analysis of the surgical specimen. We report the case of a woman aged 24 years, with symptoms of fever, vomiting and pain in the right upper quadrant. When imaging tests revealed acalculous cholecystitis, an urgent cholecystectomy was performed. Histological examination of the surgical specimen revealed eosinophilic cholecystitis. No cause of the symptoms was found.