During 12 years of surveillance in Belgium, dengue virus (DENV) infection was diagnosed in 676 of 7771 (8.7%) returning travellers by the use of ELISA, RT-PCR, and/or antigen detection. Men and women were equally infected. The mean age of the patients was 36.78 years (range, 3-77 years). Most of the infections occurred after a stay in Asia (55.9%), followed by the Americas (31.8%), Africa (7.2%), Oceania (1.0%), and Europe (0.4%). The number of patients coming from Africa increased as of 2009, to reach a proportion of 17% in 2011. The most prevalent serotype was DENV-1, followed by DENV-2, DENV-3, and DENV-4. Two remarkable increases in dengue incidence were noticed in 2010 and 2013.