Critical thinking has been identified as one of the core generic skills in the curriculum reform of the Hong Kong educational system for the new millennium. It has also been stipulated as the essential constituent for the core subject Liberal Studies in the New Senior Secondary Curriculum. In 2009, the Hong Kong Education Bureau has issued an instructional package to specify the definition and substances of the concept. In this article, this official version of the understanding of the concept will be assessed. With reference to the literature of critical thinking, critical literacy and critical pedagogy, this article will show that the official definition of critical thinking has neglected some significant aspects in the discourse of critical thinking teaching and most of the essential features of the notion of criticality. Accordingly, the article will propose a more comprehensive framework for understanding the idea of critical thinking.