The School of Science, which comprises five departments: Biochemistry, Biology, Chemistry, Mathematics and Physics, enrolls about one-quarter of the University's undergraduate and postgraduate students. In response to the needs of Hong Kong and consistent with the special mission of HKUST, the departments in the School emphasize studies in applied science. The undergraduate programs provide a strong core of instruction in both basic and applied science through course work and laboratory studies. The research-oriented postgraduate programs aim at preparing students to become scientists who are capable of carrying out independent and original research. In MSc programs, the emphasis is on coursework to strengthen students general knowledge in their chosen area of science, and to train research and technical personnel for industries.

In addition to the disciplinary undergraduate programs, the Departments collaborate with the Hong Kong Institute of Education to jointly offer four cross-disciplinary, integrated science undergraduate programs as well as the Mathematics and IT Education program. To meet society's changing needs, apart from the postgraduate programs offered by individual departments, the School has introduced the postgraduate program in Nano Science and Technology and the Atmospheric, Marine and Coastal Environment program, both of which are interdisciplinary in nature. The research-based postgraduate programs lead to the award of the Master of Philosophy (MPhil) or the Doctor of Philosophy (PhD) degrees in their respective disciplines. The interdisciplinary Graduate Diploma and MSc in Environmental Science programs, MSc in Biotechnology program and MSc in Mathematics (Financial Mathematics and Statistics) program, are self-financing programs offered to professionals to equip them with up-to-date knowledge and keep them abreast of developments in science and technology.

To enhance teaching and learning effectiveness, the School adopts innovative, interactive approaches to delivering instruction through a multi-media system that allows students to access lesson texts, charts, illustrations, animation and video clips, as well as a universal laboratory interface for on-line data taking. All departments have well-established laboratories that are equipped with state-of-the-art facilities for teaching and research. Access to the Coastal Marine Laboratory that maintains organisms in very clean running seawater is available to Marine Environmental Science students for research and education purposes.

The School's research programs are supported by a number of central facilities and interdisciplinary research institutes, of which the Biotechnology Research Institute and the Institute for the Environment are of particular relevance.