Norwegian welfare and prosperity have thrived in step with a growing petroleum sector dominating Norway's economy. However, new knowledge about the limits of the world's carbon budget and how this might render some fossil fuel reserves ‘unburnable’ now presents carbon as a potential risk. Carbon risk may be climatic, in that petroleum extraction contributes to global greenhouse gas emissions; or it could be economic, as current investments might end up as ‘stranded assets’ in a world seeking to move beyond oil. Since at least 2013, policy advocacy coalitions have employed the carbon risk concept to challenge two fundamental institutions in Norwegian petroleum resource governance: the licensing of offshore exploration areas and the petroleum tax policy. Drawing on official documents and media statements, as well as workshops and interviews with a broad range of stakeholders in Norwegian climate and petroleum policy, this paper analyses policy processes in which notions of carbon risk have been at the centre of disagreements between opposing advocacy coalitions challenging or defending the status quo of Norwegian petroleum resource governance. We identify a growing mismatch between a discernible change in Norwegian public discourse, on the one hand, and inertia in the petroleum resource management regime, on the other. Increased rhetorical connections between carbon risk and petroleum policies have caused tension and debate that challenge the governance of Norwegian petroleum production.