The results of adult mosquito collections at Paju-gun, Yonchon-gun and Kimpo-gun in Kyonggi-do and Cheolwon-gun in Kangwon-do where malaria outbreak occur, and Goyang-shi in Kyonggi -do in which was not on a outbreak region of malaria, in Korea are presented. Light traps and human bait collections were operated for adult collection from April to October, 1995. Among the total 20 species comprising 5 Genera, 7 species in Anopheles, 7 species in Aedes, 1 species in Armigeres, 4 species in Culex and 1 species in Mansonia were identified in the collection using the black light traps. The adult population densities of An. sinensis peaked at an average of 8,119.0 in Gunnae -myon, Paju-gun, Kyonggi -do, an average of 3,773.0 in Bakhak-myon, Yonchon-gun, Kyonggi-do in July and an average of 5,986.8 in Wolgot-myon, Kimpo-gun, Kyonggi-do in August in which were outbreak regions of malaria. However, lower population density of this species appeared in Kwansan-dong, Goyang-shi in the same month. On the other hand, the total of 14 species comprising 5 Genera were identified from the human bait collections at near DMZ in Paju-gun, Kyonggi-do and Cheolwon-gun, Kangwon-do in July and August. The average number of human biting mosquitoes was 1,030.8 per person in a night. The number of An. sinensis was 836.1 which showed the highest population(81.1% of all collected species) among the species in the study areas. The population of An. sinensis peaked after mid -night such as 83.0 individuals (85.6% of all species) between 24:00∼01:00 and 01:00, 124.9 (91.0%) between 01:00 and 02:00, 169.3 (93.3%) between 02:00 and 03:00, 153.6 (95.6%) between 03:00 and 04:00, and 115.9 (97.2%) between 04:00 and 05 :00 in averages.