The Union of Bulgarian Mathematicians or UBM (Bulgarian: Съюз на математиците в България, СМБ) is a learned society of mathematicians and computer scientists in Bulgaria.

[1] The Union of Bulgarian Mathematicians describes its purpose as "to bring together people who are interested in mathematics and computer science or are involved in activities related to those fields.

"[3] The predecessor of the Union of Bulgarian Mathematicians was the Sofia Physical and Mathematical Society, which was founded in Sofia on 14 February 1898, several months after the first International Congress of Mathematicians was held in Zurich in August 1897.

[3] Since 1968 the Union of Bulgarian Mathematicians holds an annual spring conference with a scientific programme.

[3] Some past presidents of the Union of Bulgarian Mathematicians, including its history before becoming independent, are:[3]