The ‘Department of Mathematics’ has been functioning almost since the inception of the University way back in 1959, teaching Mathematics to the students in the Faculty of Arts.  With the establishment of the Faculty of Science in 1967 the Department of Mathematics was formally established and since then has been teaching Pure Mathematics and Applied Mathematics as subjects for the Degree of Bachelor of Science (General). The Special Degree Programme was commenced subsequently with students specializing in one of the streams Pure Mathematics & Applied Mathematics and Pure Mathematics & Statistics in collaboration with the Department of Statistics and Computer Science. Since 2005 the Department of Mathematics in collaboration with the Department of Physics has introduced a Special Degree Programme in Mathematical Physics, which happens to be the only such programme offered by a University in Sri Lanka. The Department of Mathematics also provides opportunities for students to carry out research in Pure Mathematics, Applied Mathematics, Mathematical Statistics and Mathematical Physics leading to M. Phil. and Ph. D. degrees.

In addition to teaching and research, members of the Department have been keenly engaged in rendering their services to national institutions allied to education and have made significant contributions towards the formulation of G.C.E. (A/L) and G. C. E. (O/L) syllabi and in furthering of Mathematics education at middle school and upper school levels.

Particular mention should be made of the assistance rendered by the members of the staff to the training programmes of Mathematics teachers in secondary schools, and to the evaluation processes at public examinations.

At an international level, there has been close research collaboration with mathematicians at Kyushu University in Japan.