As one of the basic human needs, water services should be sustainable. Researches related to the sustainability of water services have been conducted in several developing countries. However, there are no identical researches in Indonesia. This paper discusses the analysis of factors that contribute to sustainability of rural water supply systems in East Java, Indonesia. Data is collected by observing rural water supply facilities, interviewing water committees and water users, and taking documentation. The data is used to build a model, which was developed from theoretical or conceptual model. The model's development uses structural equation modeling (SEM). This model can show the factors that contribute to sustainability of rural water supply systems. The sustainability is influenced significantly by nine variables; they are selection of technology, water sources, investment cost, capability of operator, availability of spare parts, operation cost, technical operation, community participation, and institutional management.
Keywords: Brantas River Basin, rural water supply system, structural equation modeling, sustainability