Indonesia's cultural diversity is evidence of differences in society. Along with the times, the sense of nationalism of the Indonesian people needs to be improved. The high number of social media use, especially YouTube in Indonesia, can be media aims to preserve culture and increase people's sense of nationalism. The purpose of this study was to determine the representation of nationalism in content wrapped in Indonesian culture with the scope of the YouTube video SkinnyIndonesian24 Pentas Swara Indonesia. The literature review contains theories and concepts regarding representation, nationalism, social media, and semiotics. This study uses a qualitative approach with an interpretive paradigm and discourse analysis methods. Peirce's Semiotics (Triadic Model) is used as a data analysis technique that examines Object as a significant reference, Representamen as a sign, and Interpretant as an interpretation. The primary data was collected from the Pentas Swara Indonesia video, while the secondary data was from literature studies and documentation. The validity of data uses triangulation of data sources. This research found a representation of nationalism in the footage of Pentas Swara Indonesia. Signs of nationalism are obtained through reference to signs that represent a sense of nationalism. The signs are from visuals (costumes, camera angles and shots, lighting) or audio (dialogues or songs) in selected scenes. The study concludes that nationalism in Pentas Swara Indonesia is a kind of effort to preserve Indonesian culture through modern art videos performance.