In the Botanic Garden Jean Massart in Auderghem (Brussels, Belgium), mosquitoes were collected with Malaise traps in 2016 and 2017, stored in 70% ethanol, and sorted out for morphological identification. Yet, in this way species-specific characters like scales may be lost, so that individuals become morphologically difficult to distinguish. Therefore, DNA-based techniques were applied for accurate species (or biotype for Culex pipiens s.s.) level identification of mosquitoes occurring in Belgium. This revealed the presence of six mosquito species, as well as two biotypes and their hybrids of Culex pipiens s.s., the most common and widespread mosquito species in Belgium. Some of the discovered species might act as vectors of arboviruses.