The increasing presence of sustainability in multiple contexts of today’s societies has led to the phe- nomenon of proliferating representations of the term. A lack of consensus towards the terminology within theory and media representations formed the base for uncertain understandings in public. Corre- spondingly, this supports the argument for investigating the public’s representation of sustainability to contribute knowledge about the current understanding of the term in public. As a platform for open and globalized communication, social media, Instagram in specific, is considered as the research field for investigation. In detail, this analysis aims to investigate large-scale user-generated data with the ‘#sus- tainability’ on Instagram as the research context, to provide knowledge on the users’ representation of the phenomenon. A mixed-method approach of computational and human-driven qualitative and quan- titative content analysis enriched the scope of the analysis to an amount of 50.000 Instagram posts. Correspondingly, the analysis of over 770.000 co-occurred hashtags within the posts allowed a contex- tualization of the phenomenon to key themes represented by the platform’s users. According to framing and agenda-setting theory as theoretical frameworks of this thesis, the findings reveal a dominant fram- ing of sustainability from an environmental perspective, in correlation to the current media agenda. Moreover, the results disclose four key meta-frames, indicating dominant patterns of representing sus- tainability in the context of Eco-Efficiency, Accountability, Consumerism, and Identity. In addition to that, the findings revealed primarily positive framing towards sustainability by the public. The theoretical contribution is an analytical investigation of sustainability representation on Insta- gram, whereby co-occurred themes help to guide further initiatives to improve behavior change and the shift towards a sustainable future.