Mosquito faunal studies were carried out in five separate wetland regions in the Czech Republic during 2004–2007, sampling with dry ice-baited and sentinel host-baited CDC traps. A total of 79,245 adults was identified, representing 23 mosquito species that belonged to the genera Anopheles, Culiseta, Coquillettidia, Aedes, and Culex. Our findings reveal that the mosquito fauna is enriched by new elements in the Mediterranean region. Historical and CDC trap data suggest that the newly-emerging potential malaria vector, Anopheles hyrcanus, has reached the northern limit of its distribution in the Czech Republic, and the important West Nile virus (WNV) vector, Culex modestus, has widened its distribution in the Czech Republic. No significant differences were observed in a total number of mosquitoes collected by traps baited with either the sentinel animals or with CO₂, although species abundance differed. A relatively higher proportion of Cx. modestus was collected in the sentinel-baited traps, while the proportion of Cx. pipiens was higher in the CO₂-baited traps.