Despite the increasing focus on incorporating the Sustainable Development Goals (SDGs) into education through curriculum mainstreaming, related research remains lacking. This study explored the representation of SDGs in Taiwan's national curriculum in terms of selection and organization. Through a content analysis of the social studies and natural sciences curriculum guidelines, the findings revealed that SDG-related content comprises a minor part of the guidelines and is not well organized, possibly due to limitations on discipline characteristics and curriculum types. A subtle but complex implicit curriculum reflects neoliberalism, which addresses SDG-related issues through market mechanisms and shifts the focus from power, politics, and citizenship to consumers' choices and lifestyles. The results provide a reference for policymakers and educators in re-examining underrepresented SDGs and dimensions and organizing them coherently. They also bridge the gap between the international framework and national curricula, laying the foundation for international comparisons, discussions, and debates on ESD.