Transparency, privacy, and information quality assurance are profound issues that often emerge due to the publication or use of open data. Realizing the three values are important, and the design of open government data portals should be able to accommodate the values. However, how the open data portals should be designed in order to accommodate the three values is still unclear. Existing principles of open government data focus on the data itself, rather than how open government data portals should be designed with regard to the values of transparency, privacy, and information quality. Therefore, there is a need for explicit design principles for incorporating these values into the design of open government data portals. This research does qualitative research on open government data portal design principles. The approach taken involves reviewing literatures to find out the dimensions of transparency, privacy, and information quality which are relevant to open government data portal design. Next, design requirements from open government data portals are obtained through interviewing five academic researchers from TU Delft while focusing on the dimensions of transparency, privacy, and information quality. Then, design observation is done on five selected open government data portals, focusing on the implementation of design requirements acquired in the previous phase of the research. Lastly, principles are formulated from the findings obtained from each phase of this research. The result of this research project is a set of design principles which serves as a guideline on how to design open government data portals that incorporate transparency and privacy while ensuring information quality.