Introduction. Due to the risk of local transmission, imported cases of dengue fever pose a potential public health problem in areas where the Aedes albopictus mosquito is present. Method. Using a capture-recapture method, we estimate the annual incidence of dengue fever and the completeness of two surveillance systems: mandatory reporting and a network of laboratories. Results. The number of imported dengue cases in mainland France from 2007 to 2010 is estimated at over 8,300, including 4,500 in 2010 during the large-scale epidemics that occurred in the French West Indies. During these four years of surveillance, 327 cases occurred in the Southeast during the vector’s active season (May to November), including 234 in 2010; most cases were potentially viremic. Estimates of the completeness of mandatory reporting and the laboratory network are 9% and 38%, respectively, over the entire period and territory; they are higher in the Southeast from May to November, at 32% and 69%, respectively. Conclusion. The coverage of national surveillance systems is satisfactory in areas and during periods critical for metropolitan dengue surveillance. The number of imported cases may increase due to the global spread of dengue, its hyperendemic status in the Caribbean, and increased travel. (R.A.)