Considering that the role of local people in the development of sustainable tourism is crucial, it is of great importance to continuously measure, observe and monitor their perception and attitude towards tourism activities in their community. Taking into account the economic, socio-cultural and environmental impacts of tourism, this study examines the role of residents’ perceptions of these impacts, their level of information about tourism activities and socio-demographic characteristics in determining the extent of their support for tourism development. Istria was chosen as the study area because it is the region with the highest number of tourists in Croatia. Due to the continuous increase in the number of tourists, there is a need to find out how residents deal with such trends and support such development. A field study was conducted, in which 865 completed questionnaires were correctly recorded. The collected data were analyzed using the methods of descriptive statistical analysis, reliability analysis and regression analysis. The results show that the more positive the perception of economic and socio-cultural impacts of tourism, the greater the support of local people for further tourism development. In contrast, perceptions of environmental impacts of tourism and socio-demographic characteristics of residents were not found to be significant predictors of residents’ support. An interesting result is the fact that there are no significant differences in support for tourism development between residents living on the coast of Istria and those living far from the sea.