The county Health Care Agency says the Fountain Valley man died last week from influenza B-related disease. There are no other details.
Influenza A and B cases have been reported in the county.
Those at highest risk are young children, pregnant women, senior citizens, the morbidly obese, health care workers, children and adolescents receiving long-term aspirin therapy and people with chronic diseases, including heart disease, asthma, lung diseases or diabetes.
Health officials say a flu vaccine is the best protection against flu viruses. The flu season hasn't peaked in Orange County and experts say there is still time to get vaccinated.