Health officials say in a news release Thursday that the death occurred in Lincoln County.
The Health Department also reported nine new cases of the virus. The new cases were reported in Copiah (1), Hinds (2), Lawrence (1), Lincoln (1), Rankin (3) and Smith counties, bringing the state total for 2012 to 85 cases and two deaths.
The first death occurred in Smith County.
In 2011, Mississippi had 52 cases of West Nile virus, with five deaths.
Health officials say residents should take precautions like removing sources of standing water where mosquitoes breed and to wear long pants and sleeves in mosquito-prone areas during peak times from dusk until dawn. Mosquito repellent is also recommended.