In the old Hungarian language, the name of the city (Böszörmény) probably referred to a Turkish speaking Muslim ethnical group, which conducted an important commercial and economic activity in the Árpád age. This community was destroyed during the Mongol invasion, but the settlement known as Nagyböszörmény became an important commercial centre by 1248.
In 1410 King Sigismund raised the settlement to the rank of a market town. In 1605 the Transylvanian Prince Bocskai provided lands and noble titles to 9254 hajduk mercenaries with his Letter of Privilege, which is the Magna Charta of the Hajdúság. At this time Böszörmény was not included among the places which were given to the hajduks, but Kálló was.
For many years the hajduks had been in conflict with the imperial guard of the castle, which caused Gábor Báthory to resettle and grant privileges to hajduks on his properties of Böszörmény with the Letter of Exchange, dated 13 September 1609.
From the middle of the 17th century Böszörmény began to develop significantly and in 1669 when the Hajdú District came into existence, it became its seat until 1876, when a new county was established. It can be safely said that Hajdúböszörmény counts with a rich past in addition to a vivid present.