The man’s first symptoms were noticed on 3 September and reported on 6 September, Doctor Francis Charlet told a press conference on Friday.
After undergoing treatment he has been cured and returned home, Charlet said.
Dengue is a mosquito-born disease generally found in the tropics but this case is the second one of local origin reported this year.
The first, declared on 21 August, was in the same region, the Var, but health officials say there is no connection between the two.
A case of illness is considered to be of local origin when the patient has not travelled to an area where the disease is common in the preceding fortnight.
Dengue is carried by several kinds of mosquitoes of the aedes genus, originally found in tropical and subtropical regions but now present on all continents, including Europe.
Charlet said the two cases have probably appeared in the Var because mosquitoes are common there, while noting that several “imported” cases have been identified there.
Mosquitoes were found in several places that the man frequented and a control programme was carried out on Friday.
Homes in the area were also visited to check for further cases of the virus.