Current academic research bodies on STEM education focus on five perspectives of student ability enhancement, teacher training, curriculum integration, pedagogy and curricular implementation in intra-national/cross-national comparative studies. Noteworthy, there has been no comprehensive policy analysis of STEM education in secondary school curricula in Hong Kong. For STEM is not formally documented into school curricula and students mostly join inter-school and international STEM project competitions. International literature reveals that conceptions of STEM education are still fuzzy. In this paper, a 2 X 3 matrix is utilized to evaluate the extent of implementing STEM education in mainstream secondary schools in Hong Kong, and to envisage contextual difficulties and obstacles against STEM education. This paper then leads conceptual discussions on integrated approaches, draw policy implications and recommend further research agendas. Copyright © 2022 Asia-Pacific Society for Computers in Education.