The application of geographic information systems (GIS) technology to malaria surveillance presents an opportunity for focusing intervention and prevention activities in the areas most affected. We used GIS technology to map the prevalence of malaria in the Wosera Health and Demographic Surveillance Site, East Sepik Province, Papua New Guinea (PNG). Malaria, demographic and GIS data collected between 2001 and 2003 were aggregated and analysed. This was achieved by geo-coding or linking the prevalence and demographic data to the village location. All GIS manipulation and cartographic displays were performed in MapInfo. The results suggest that malaria is endemic with high prevalence as observed across the 3 surveyed years. The optimized implementation of GIS can be of tremendous benefit in the fight against malaria and other public health challenges in PNG.