The imported dengue cases has increased recently, and 162 autochthonous dengue cases were reported in 2014 in Japan. Since late 2014, the Zika virus has spread widely throughout the Americas. The surveillance for the invasion of these mosquito-borne infectious diseases is indispensable. Japanese encephalitis is found throughout Asia and there is still a risk of human infection in Japan. Over 3,500 species of mosquitoes have been documented through- out the world, and over 100 in Japan. Among these, we suggest the following four are the major vector mosquitoes in Japan: Culex pipiens, Culex tritaeniorhynchus, Aedes albopictus, and Anopheles spp. Here, I introduce the characteristics of each vector mosquito species, with an aim to aid the prevention and control of mosquito-borne infectious diseases.