Background and Purpose: Norovirus has the role of one of the main causative agents of gastroenterocolitis both in sporadic cases and epidemics. Reports of Norovirus outbreaks, individual cases and hospitalizations of the Croatian National Institute of Public Health were observed as well as school data base of the Ministry of Science, Education and Sports. Results: The characteristics of NoV outbreaks registered in Croatia in 2006 were presented in the aim of approximation of transmission routes and impact on health. NoV transmission by water in the particularly vulnerable school population causes serious repercussions on the health. The significance of Norovirus (NoV) in the Croatian population is indirectly proved by an 8.2% share of patients in all alimentary and hydric outbreaks. Conclusion: Taking into account this outcome, NoV should be reported as a separate entity, as the causative agent of communicable gastroentercolotis of nonbacterial etiology in our country.