Background: Involvement of the extrahepatic biliary outflow tract in patients with EBV infection is already known in the literature as EBV induced acalculous cholecystis. Case report: A 11-year-old girl with EBV infection was initially diagnosed on clinical grounds and the diagnosis was confirmed by positive IgM antibodies to EBV viral capsid antigen (VCA) and a positive Monospot test. The patient also complained about abdominal pain during the illness course, mainly at the palpation of the right upper quadrant of the abdomen with a positive Murphy sign. Gallbladder involvement was disclosed by using ultrasound imaging (thickened oedematous gallbladder wall of 7,3 mm without dilation of the biliary tract). A radioisotopic cholangiography was also performed which showed that the emptying of gallbladder was not accomplished even after the administration of a fatty meal and ejection fraction was negligible at 45 min. A repeated ultrasonographic examination, ten days later, revealed normal thickness of the gallbladder wall. A repeated cholescintigraphic examination of the gallbladder, one month later, showed that the motility of the gallbladder has been considerably improved since the initial examination with an ejection fraction calculated to > 70%, although emptying was not fully accomplished at the end of the study at 60 minutes.Conclusion: Based on the scintigraphic data of our patient we consider that impaired gallbladder contractility in EBV infection cases actually represents biliary dyskinesia and by no means acalculous cholecystitis, a term that may misinterpret the data.