The Department of Mathematics consists of three divisions, mathematics, mathematical statistics, and computer science and scientific computing Mathematics was one of the first subjects taught at the newly founded Stockholm university in 1878 and the first professor at the university was Gösta Mittag-Leffler, with an appointment in mathematics. Sonja Kovalevsky, the first woman to be employed as a full professor of mathematics, was another prominent early member of the department.

The Department has a well equipped library which is probably one of the finest in northern Europe. One could say that the library is to a mathematician what the laboratory is to an experimental scientist.

The Department is situated in beautiful buildings from the 1910's that used to house the Veterinary School. The area around Brunnsviken is scenic and is also known from literature and history. The celebrated 18th century songwriter and poet Carl Michael Bellman mentions Brunnsviken on several occasions in his poetry.