Mosquito-borne diseases impact humans in almost every part of the world since mosquitoes of medical importance are widely distributed. Besides arboviruses, mosquitoes are also vectors of other pathogens of significant public health concern, including protozoans, filarial parasites and to a lesser extent bacteria. Vector control measures help reduce the spread and impact of these diseases. In this framework, the Medical Component of the Belgian Armed Forces has launched a pilot project to investigate the Culicidae biodiversity at foreign sites where the Belgian Army is deployed. Since the project started, adult specimens were collected on military bases in Jordan, Gabon and Mali. A comprehensive list of mosquito species occurring in each of these countries was established based on the available publications and reports, and available DNA-sequences deposited on online reference databases (BOLD and GenBank) were evaluated for their usefulness in identifying mosquito vectors by DNA barcoding. In total, 178 specimens were identified using DNA-based methods. Among these, important disease vectors were identified, including Aedes aegypti, Aedes albopictus, Culex quinquefasciatus, Culex pipiens, Culex perexiguus, Anopheles coluzzii and Anopheles gambiae. Some of these species are known to transmit the West Nile and the Rift Valley fever viruses in Africa, while others are important vectors for Wuchereria bancrofti (causing lymphatic filariasis) as well as for the yellow and dengue fever viruses in areas where the mosquitoes were collected. Besides providing essential information to set up mosquito control measures (preventive or active), this biodiversity study emphasizes the importance of treating army equipment appropriately when returning to Belgium in order to avoid unintentional introductions of exotic mosquito disease vectors.