A 65-year-old from Middlesex County and a 73-year-old from Burlington County both had headaches and fevers.
The Middlesex man has recovered and been released from a hospital. The health department says the Burlington man remains seriously ill and in a health-care facility.
The virus spreads through mosquitoes who get it from infected birds.
The worst year for the virus in the state was in 2003 when there were 32 confirmed human cases.