Usutu virus (USUV) was detected in 11 Culex pipiens mosquito pools collected in 2015 in Camargue (France) using quantitative real-time RT-PCR assays. Phylogenetic analysis of recovered virus sequences identified USUV lineages Africa 2 and Africa 3, demonstrating the simultaneous occurrence of different strains within the mosquito population. This is the first report on USUV in mosquitoes from France that concurrently accompanied the emergence of Usutu virus in blackbirds and a human case in France during 2015/2016.