The faculty of science was established in 1961 as the second faculty of science in Sri Lanka and it is one of the eight faculties of University of Peradeniya. At the present time the science faculty consists of eight academic departments namely Department of Botany, Chemistry, Geology, Mathematics, Molecular Biology & Biotechnology, Physics, Statistics & Computer Science, Zoology and Computer Unit and Science Education Unit. The Science faculty enrolls 400 students annually. Currently, the student enrolment stands at about 1000 undergraduate and 200 postgraduate research students. Also there are 110 academic and 120 non-academic members of staff in the faculty.

The Department of Botany is one of the foremost departments established at the faculty of Science which carries a reputation for maintaining high academic excellence and a strong research culture. This Department has evidently broaden the scope of the teaching program by enhancing to meet the novel developments of the field.

The Department of Chemistry was established in 1960 and located in the middle of University of Peradeniya. This Department is recognized as the premier research institutes in the country. The department consists of a team of highly professional staff.

The Department of Geology is the only full-fledged Geology Department in the University system and this department has improved vigorously. Furthermore the excellence in teaching and research in Earth Science related subjects belongs exclusively to this department. The Geology department also consists of a well-qualified academic staff.

The department of Mathematics was initially established in the Faculty of Arts as a teaching unit. With the establishment of the Faculty of Science in Peradeniya, the department of Mathematics started to function in the present location. The Department offers a high quality Special Degree Programme which has an international recognition.

The Department of Molecular Biology and Biotechnology (MBB) has evidently contributed to the Biological Sciences by providing Science undergraduates with rigorous training in Molecular Biology and Biotechnology. This department along with the experienced academic staff have involved in the training of undergraduates as well as undertaking research in many areas of Molecular Life Sciences.

The Department of Physics can be considered the forerunner of the physics education and research in Sri Lanka. The Department is recognized locally and internationally for its research capabilities and professional services. Furthermore well-equipped laboratories and facilities are accessible to researchers.

The Department of Statistics and Computer Science can be considered as a rapidly developing field in the faculty of science. Since its establishment in 1996, it has widened its capacity in terms of facilities as well as the number of students it caters over the years.

The Department of Zoology was established in July 1961, and this department promotes the study of basic and applied aspects of Zoology. A comprehensive course in Zoology is conducted by a highly professional staff.

Overall, the Faculty of Science caters courses for General and Special Bachelor of Science (B.Sc.) Degrees. The Faculty at present offers Special degree programs in Botany, Chemistry, Computer Science, Geology, Mathematics, Molecular Biology & Biotechnology, Physics, Statistics and Zoology. This faculty can be considered the enhancing agent that widely open doors to the technological advancements.