Background and Purpose: Mosquitoes (fam. Culicidae) are significant molestants, but are alos capable of transmitting different diseases. The coastal regions of Croatia were original (autochthonous) areas of malaria during the first half of the 20th century. Despite malaria eradication in the 1960's, the mosquitoes capable to carry plasmodium still represent a potential treat to human and animals in rural as well as in urban regions. the goal of the study was to obtain better insight into composition and distribution of moquito species, especially those of particular medical importance. Material and Methods: Mosquitoes were collected in their larval stage, and subsequently adult mosquitoes hatched. We used CDC traps with dry ice as an attactant. Our faunistical investigations during 2000-2004 showed the presence of 27 species in Dalmatia (part of the coastal area of Croatia). From Maslenica Bridge to Prevlaka, we observed more than 50 localities. The investigations were carried out from April to November each year. Results and Conclusions: Among 27 species present in the investigated area, 10 of them had medical importance. These species were: Anopheles messeae, Anopheles maculipennis, Anopheles saccharovi, Anopheles claviger, Culex pipens, Ochlerotatus cantans, Ochlerotatus caspius caspius, Ochlerotatus detritus, Aedes vexans and Coquillettidia richiardii. Some of these species had played an important role as vectors of malaria in Dalmatia. Breeding sites were quite varied: edges of lakes, marshes, ponds, flooded meadows, abandoned houses, rock-holes, containters, tires etc. Water was mostly stagnant, sometimes rich in organic matter. These breeding sites coult be either permanent or temporary, either shaded or sunny with fresh or brackish water. Of special concern is the spreading of exotic species, such as Asian tiger mosquito (Aedes albopictus), a natural vector of dengue, and several arboviruses (e.g. Yellow fever and West Nile virus), and Dirofilaria immitis which was introduced in Europe during the last two decades deu to maritime transportation of tires. This mosquito was found for the first time in Croatia (Zagreb) a few months ago. For these reasons, we considered of crucial importance to monitor the coastal area of Croatia - a climatic area suitable for permanent Aedes albopictus habitat.