The Vector Control Branch of the Hawaii State Department of Health has accumulated a large volume of written inspection data on mosquitoes of public health importance. The objectives of this study are to conduct a survey of the occurrence of mosquito complaints on Oahu over a 10 year period, graphically compare mosquito occurrence within and between district/areas, and correlate mosquito occurrence and distribution with season. Mosquito data were drawn from inspection reports from 1990-1999, population information was obtained from Hawaii Census and State of Hawaii Data Books, 125 district/area geographic locations were created, and mosquito occurrence and distribution were adjusted for population and mapped using ArcView GIS 3.2. Most of the mosquito activity was found within the central, south and east urban districts. Drier areas from Kalihi Kai to Portlock showed the highest number of complaints, and the levels of mosquito activity were highest during the winter, spring and summer. The primary mosquito species identified was Aedes albopictus, the Asian tiger mosquito, and the main breeding sources were various containers, plus bromeliad plants. Gardening activities, irrigation, poor drainage, toys holding water, and man-made ponds and pools all contributed to mosquito breeding. Aedes albopictus populations are being maintained in urban districts by human activities. As a result, dengue transmission is possible in the drier, urban areas of Oahu. These results indicate that educational programs should be carried out in late fall and early spring, and that residential mosquito surveys may be concentrated in a limited number of district/areas.