The bilateral relationship between Indonesia and Malaysia has been established since 1957. Indonesia and Malaysia referred as countries with a strong historical background and related to various of disputes over time that appeared in and off media. As countries with a shared identity, both has experienced many tensions which leads to conflicts among them. Cultural tension believed to be the trigger of the tension which appeared until today. Soft power is considered to be the diplomatic action for both countries. The purposes of this research is to analyze the historical background of the tension between two countries, find out the influence on the role of media, and evaluate the culture ownership implementation in both countries. However concepts that is used in the thesis are National Identity, Culture, Foreign Policy, Interdependence and Bilateral Relations. This research used Qualitative method. Data are obtained through newspaper articles, journals, book that are used as references, and official website browsing. From the data and analysis it is found that the tension between Indonesia and Malaysia which appeared regarding its cultural heritage caused by an internal factor that is the shared identity that are implemented as serumpun countries and leads to both people's unsatisfied reaction until today. The role of media is also the trigger to the tension among the society. However, the domestic law that binds the cultural ownership in both countries are still weak, member states of ASEAN often prefer bilateral approach to maintain and preserve their cultural heritage.