Since 2002, Culicoides populations were monitored in France using sentinel UV traps. Number and repartition of traps have changed depending on the epidemiological situation. Surveillance system was first focused on the Mediterranean region and dynamics of Culicoides imicola, and currently covers the whole territory with 160 traps operated weekly or monthly depending on the season. The diversity of Culicoides depends mainly on the ecoclimatic zone. ln the Mediterranean area, Cuticoides newsteadi is the dominant species associated with C. imicola in Corsica. The surveillance system detected erratic specimens of C. imico!a in 2003 in the French mainland and the establishment of populations since 2004 in the Var department. ln non-Mediterranean areas, Palearctic species of the subgenus Avaritia, i.e. the Obsoletus complex, Culicoides dewulfi and Culicoides chiopterus, are largely dominant with about 80% of ail collected specimens. Among this subgenus, the proportion of C. dewulfi and C. chiopterus decreases with the latitude and these species become rare in south-western France. Data of population dynamics were obtained for several years, especially in Corsica. The seasonal abundance depends on species, region, and year, with important interannual variations. The dates of the start and the end of the Cutieoides activity vary between regions, and seem to be driven mainly by temperature. ln conclusion, wide-area and long term entomological surveillance allows the establishment of correlations between species distribution, population dynamics and climatic and ecological factors for a better understanding of vector presence and dynamics.