We report the first pediatric fatal case of Hepatitis A virus (HAV) and dengue virus (DENV) co-infection. A 4-year-old boy who had a partial recovery of HAV infection but with subsequent DENV infection; the condition was complicated by acute fulminant hepatic failure, and death. The risk of DENV co-infection should be considered as cause of acute fulminant hepatic failure in pre-existing Hepatitis A infection.