Elementary school is a place that can result in increase of dengue disease among children because of environmental factors, potential transmission, the absence of good environmental management system and some control efforts which are no longer effective. This study aimed to determine factors that potentially against transmission of dengue hemorrhagic fever in state elementary school, so the early warning system can be enforced. Type of study was analytic with cross-sectional design. The study was conducted in 91 state elementary schools in Yogyakarta City in 2014. Variables in the observation are virus serotype DEN, insecticide resistance, the density of vector and physical condition of schools. Data analysis used descriptive and correlation-regression (a = 5%). Results showed that there were eight schools with dengue virus serotype 2 and 3 mosquitoes declared to have mild and moderate resistance to organophosphate, the school environment was susceptible to transmission of dengue hemorrhagic fever based on the container index, house index, breteau index and ovitrap index, temperature and humidity inside and outside were potential to the high density of eggs, wire netting was not installed on ventilation and the very close distance between the buildings could lead to transmission.