The rate of population growth and the increase in food needs for consumption have made the need for paddy fields higher. On the other hand, the pressure on paddy fields is quite intense so that the conversion of paddy fields is quite challenging to be controlled. Moreover, the concerns about food security and food sovereignty have become critical issues. The high demand for land utilization has caused pressure on paddy fields in the Citarum watershed. The objective of this study is to build a model for maintaining paddy fields in the Citarum watershed. The study was conducted from June to September 2015. The method of this research is a modelling using system dynamics approach by simulating time series data. From the simulation, it can be concluded that the rate of conversion of paddy fields will still be high if there is no specific policy in its protection. This fact can be seen from various scenario conditions, either in existing circumstances, in the optimistic scenario, as well as in a moderate scenario. The strategy that can be done is that paddy fields should be specially protected or owned by the government to minimize the rate of conversion.