Vertigo in children is relatively under examined in the literature. Among its causes, vestibular neuritis (VN) represents only 2% of cases, with its etiology remaining unknown. We report for the first time a 4-year-old boy with vestibular neuritis and serological results compatible with adenoviral infection. Serological diagnosis was performed on the basis of a rise and consequent normalization of complement fixation (CF) titers of the plasma antibodies. Although we were not able to detect exactly when the infection started, we were able to detect an increased level of adenovirus antibodies by CF titers, followed by a decrease (i.e. 1/16, then 1/8, then <1/4) during the recovery. This is typical of a resolving infection. Furthermore, that this increase in antibodies was specific to an adenovirus infection was suggested by the observation that we did not detect increases in antibodies to other common viruses (i.e. herpes simplex and zoster viruses, Epstein-Barr virus, cytomegalovirus, influenza and parainfluenza viruses). This allows us to exclude the chance of nonspecific antibody activation. We concluded that, although our data do not formally demonstrate an involvement of adenovirus in VN, they suggest such an involvement. This may be of interest, given that a viral etiology for VN has been proposed but not definitively proven.