In carrying out water allocation planning in a comprehensive, integrated, and sustainable manner, a complete, appropriate and practical database model is needed so that it can be optimally applied. The database system model in this study consists of several tables that are linked in an Entity Relationship (ER) Diagram. The table that is the center of the running process is the neraca_district table (water service area). The table gets input from the supply, demand, potential and water district tables. Calculation of water allocation must pay attention to aspects of space, time, quantity, and quality. Normalizing data and arranging it in separate tables so that data duplication does not occur is an important stage in compiling a database model. The water allocation database system model is highly dependent on the ER Diagram because the relationship between one table and another will affect the operation of the system. The database system model used is the parent-child structure because it is able to build a chain allocation system, meaning that the results of one water district can be an input for the water district downstream. This research has been able to build a model spatial database system for planning water allocation by considering the aspects of space and time. So that the condition of water allocation results of the analysis can be seen directly because the database system is processed by building relationships between entities in the system.